The Not-So-Changing Geography of U.S. Elections

On November 3, 2020, Democrats Joe Biden and Kamala Harris were elected president and vice president, respectively, of the United States. According to data from Dave Leip’s essential Atlas of U.S. Presidential Elections, the Biden-Harris ticket won 51.3% of the nearly 158.6 million votes cast. Turnout shattered the previous record of 137.1 million votes cast in 2016: 15.6% more votes were cast for president in 2020 than in 2016. The incumbent Republican president and vice president, Donald Trump and Mike Pence, won 46.8% of the vote, with the remaining 2.0% going mostly to the Libertarian and Green tickets

While the 4.5 percentage point (“point”) margin for Biden-Harris over Trump-Pence—7.1 million votes—was solid, it is the Electoral College which determines the winner of presidential elections. Despite objections to the counting of the votes from individual states and an armed insurrection aimed to stop the Congressional certification of Electoral Votes (“EV”), the Biden-Harris ticket was awarded 306 EV—36 more than necessary—to 232 for Trump-Pence.

In many ways, the 2020 presidential election was a near-perfect encapsulation of recent presidential elections. Between 1992, when Democrats Bill Clinton and Al Gore were elected president and vice president, ending 40 years of Republican White House dominance, and 2016, the Democratic presidential ticket averaged a 3.6-point winning margin and 313.7 EV, very close to 4.5 points and 306 EV.

Biden-Harris improved on the 2016 Democratic margin in the national popular vote by 2.4 points, winning 16.4 million more votes than the ticket of Hillary Clinton and Tim Kaine; Trump-Pence won 11.3 million more votes, while third party candidates won 5.2 million fewer votes. Moreover, across the 50 states and the District of Columbia (“DC”), the Democratic ticket improved by an average of 3.1 points! In the EC, as Table 1 shows, Biden-Harris carried five states Clinton-Kaine lost in 2016: Arizona, Georgia, Michigan, Pennsylvania and Wisconsin; no states flipped the other direction.

Table 1: States with Presidential Election Margins <5.0 Points in 2016 and/or 2020

StateEV2016 Margin (Dem-Rep)2020 Margin (Dem-Rep)2020-2016
North Carolina15-3.7-173,315-1.3-74,483+2.4+98,832
New Hampshire40.4+2,7367.4+59,277+7.0+56,541

Clinton-Kaine won Virginia by 5.3 points in 2016; four years later Biden-Harris won the state by 10.1 points, a 4.8-point jump. The shift in Texas was similar, from a 9.0-point loss to “only” a 5.6-point loss, a 3.4-point improvement. In fact, Biden-Harris did better than Clinton-Kaine in every close state except Florida, losing by 258,775 votes more than in 2016. Overall, the only other states where the Democratic margin was at least 0.1 points worse in 2020 were Arkansas (-0.7), California (-0.8), Utah (-2.4) and Hawaii (-2.7). By contrast, Biden-Harris improved by at least 6.0 points (roughly double the state average) in the close states of Maine (6.1), New Hampshire (7.0) and Colorado (8.6), as well as Massachusetts (6.3), Connecticut (6.4), Maryland (6.8), Biden’s home state of Delaware (7.7) and Vermont (9.0).

Had Clinton-Kaine flipped just 77,736 votes in Michigan, Pennsylvania and Wisconsin in 2016, Democrats would have retained the White House, 278-260. By the same token, had Trump-Pence flipped just 65,009 votes in Arizona, Georgia, Wisconsin, and the 2nd Congressional District of Nebraska (“NE-2”), they would have been reelected, 270-268—while still losing the national popular vote by 4.5 points. Wisconsin, which shifted only 1.4 points—43,430 votes—toward the Democrats, was a key pivot state in both elections, with Pennsylvania right behind.


To better understand the relative partisan leans of each state, I developed 3W-RDM, a weighted average of how much more or less Democratic than the nation as a whole a state voted in the three most recent presidential elections. Basically, it is what I estimate the state-level margin between the Democratic and Republican nominees would be if they tied in the national popular vote. Note, however, that 3W-RDM (plus national popular vote) has missed the actual state-level result by an average of 5.3 points in recent elections. Figure 1 and Table 2 show current 3W-RDM for every state, based upon data from the 2012, 2016 and 2020 elections. Table 2 also lists 3W-RDM based upon data from 1984-92 and 2008-16.

Figure 1: Current State Partisan Lean, Based Upon 2012-20 Presidential Voting

Table 2: Current and Historic State Partisan Lean (3W-RDM), Sorted Most- to Least-Democratic

State2020 EV1984-922008-162012-20Ave. Change 1992-2020
New York2910.821.620.21.3
Rhode Island415.
New Jersey14-
New Mexico52.
New Hampshire4-
North Carolina15-7.0-6.0-5.80.2
South Carolina9-13.9-15.7-15.9-0.3
South Dakota3-5.5-25.8-29.6-3.4
North Dakota3-12.7-29.4-35.4-3.2
West Virginia59.2-35.5-41.4-7.2
AVERAGE -1.3-4.6-5.1-0.5

The core Democratic areas are primarily where they have been for 30 years: New England (average 3W-RDM: D+15.2), the Pacific Coast minus Alaska (D+12.4), the mid-Atlantic minus Pennsylvania (D+22). These 15 states and DC contain a total of 183 EV. Add the Midwestern states of Illinois (20 EV) and Minnesota (10), and the southwestern states of New Mexico (5) and Colorado (9), and the total rises to 226 or 227, depending upon Maine’s 2nd Congressional District (“ME-2”). This is the current Democratic presidential baseline, 44 EV from 270.

The core Republican areas are also primarily where they have been for 30 years: Mountain West plus Alaska minus Colorado (R+29.2); the six states running south from North Dakota to Texas (R+26.9); the five states in the western half of the Deep South (R+25.8); the border states of Missouri, Kentucky and West Virginia (R+30.3); and the Midwestern states of Iowa, Indiana and Ohio (R+13.1). Add the southern Atlantic states of North Carolina, South Carolina, Georgia and Florida, plus Arizona, and the total is 258 or 259 EV, depending upon NE-2. Each of these 27 states is at least 5.5 points more Republican than the nation, making it the current GOP presidential baseline, just 12 EV from 270.

Two states totaling 22 EV would be balanced on a knife’s edge: Michigan and Nevada. In 2016, they split, with Republicans winning the former and Democrats winning the latter. Biden-Harris won both in 2020.

That leaves two states totaling 30 EV—Pennsylvania (R+2.3) and Wisconsin (R+2.4); they lean more Republican than the “core” Democratic states of Minnesota and New Hampshire. Add them to the “core” Republican 258 EV, and Republicans enter a presidential race tied in the national vote—or even a point behind—with a minimum of 288 EV, 18 more than necessary. Michigan, Nevada, NE-2 and ME-2 would get them to 312.

I made this same point here, when I used a simple ordinary least squares (“OLS”) regression model of EV and national popular vote margin to show that in a dead-even national election, Republicans would—on average—be favored to win the EC 283-251, with four EV going to third-party tickets. Adding data from 2020 does not materially alter this estimate, which is essentially Republicans winning their 258 EV plus Pennsylvania and Wisconsin: 288 EV. Democrats then win their core states plus Michigan, Nevada, ME-2 and NE-2: 250 EV.

Here are the updated OLS regressions:

Democrats:               Electoral Votes = 1232.9*Popular Vote Margin + 250.98

Republicans:            Electoral Votes = 1229.2*Popular Vote Margin + 283.04

Simple algebra shows Democrats need to win nationally by 1.5 points to be on track to win 270 EV, while Republicans could lose nationally by 1.1 points and be on track to win. Put another way, Republicans could theoretically lose the national popular vote by 2.3 points and still win 288 EV, given the imbalance in the Electoral College.

Paradoxically, however, Democrats have won the EC in five of the last eight presidential elections, because they win the national popular vote by large enough margins. The 3.5-point average margin in those eight elections translates to an estimated 294 EV, on average: winning their core 226, plus Michigan, Nevada, ME-2, NE-2, Wisconsin, Pennsylvania (280 EV total) plus one of North Carolina, Arizona or Georgia. As we saw, the Biden-Harris ticket won all but ME-2 while adding Arizona and Georgia, losing North Carolina by just 1.3 points.

This imbalance has been getting worse over time. In the mid-1990s, after the Republican ticket won by landslides in 1984 and 1988 and Clinton-Gore won by a slightly smaller landslide in 1992, the average state was only 1.3 points more Republican than the nation, far lower than the roughly 5.0 points of recent elections. In a dead-even national election—essentially what happened in 2000—Democrats would have had a slightly higher base, ~230 EV from 18 states plus DC at least D+2.0, with the ~30 EV of Michigan, Connecticut, Maine and Delaware within 1.0 points either way. Democrats would start closer to 250 than 230 votes in this scenario, though there would still be ~275 EV from 27 states at least R+2.0; throw in Montana (R+1.6) and the total increases to 278. Still, Democrats were far closer to parity in the EC in the mid-1990s than they are now.

What changed?

Figure 2: Average Change in State Lean Since 1984-92

As Figure 2 clearly shows, the strength of state-level partisanship sharply increased over time: Democratic states become somewhat more Democratic, while Republican states became dramatically more Republican. Not only did the average state shift 3-4 points more Republican, relative to the nation, but the variance widened. After the 1984-92, the standard deviation—a measure of how narrowly or widely values are spread around the mean—increased from 14.4 to 23.4 after the 2012-20 elections. Moreover, consider states at least 3.5 points more partisan than the nation. In the mid-1990s, those states averaged D+12.8 and R+12.0; today, those values are D+19.5 (213 EV) and R+22.4 (259 EV).

The biggest pro-Democratic shifts, based upon the average three-election-cycle change in 3W-RDM since 1984-92, occurred in Vermont (average: D+3.2), the Pacific states of California and Hawaii (each D+2.7), and the mid-Atlantic states of Maryland, New Jersey, Virginia and Delaware and New York (mean: D+2.0). Colorado, Nevada, and the remaining New England states except Maine also shifted noticeably more Democratic. At Colorado, Nevada and Virginia even switched from core Republican states to core Democratic/swing.

But these shifts are miniscule compared to two blocks of Republican states. The first block I call the “upper interior Northwest”: Idaho, Montana, Wyoming and the Dakotas. These five states became an average 3.2 points more Republican every cycle since the mid-1990s. The second block I loosely call “Border,” though I could also call them “White, Culturally Conservative”: Oklahoma, Missouri, Arkansas, Tennessee, Kentucky and, most extremely, West Virginia. These six states became an average 5.3 points more Republican every cycle since the mid-1990s. West Virginia, in fact, is almost in a category by itself. Following the 1992 presidential election, when Clinton-Gore won it by 13.0 points, it has become an astonishing 7.2 points more Republican each cycle since then; Trump-Pence won it in 2020 by 38.9 points, a 51.9-point pro-Republican shift!

In fact, seven states—Arkansas, Kentucky, Oklahoma, South Dakota, Tennessee, West Virginia and Wyoming—shifted further Republican over 28 years than any state shifted Democratic over those years. West Virginia is also joined by Arkansas, Iowa, Missouri, Pennsylvania and Wisconsin as states that shifted from core Democratic to core Republican/pivot states.

As for why states shifted strongly Democratic or Republican, I wrote here about the growing partisan divide between white voters with (Democratic) or without (Republican) a college degree. Other explanations include self-sorting by geography (Democrats to the coasts, Republicans to “flyover” country) and information (Democrats from traditional media, CNN and MSNBC; Republicans from right-wing media and Fox News).


Thus far, I have only looked at presidential elections. Table 3 lists the percentages of United States Senators (“Senators”), Governors and Members of the United States House of Representatives (“House Members”) who are Democrats in the core Democratic, swing/pivot (Michigan, Nevada, Pennsylvania, Wisconsin) and core Republican states. Data on the partisan split of each House delegation, based upon the results of the 2020 elections, may be found here.

Table 3: Democratic Percentage of Senators, Governors and House Members in Three Groups of States

GroupSenatorsGovernorsHouse Members
Core Democratic (n=19)97.4%*78.9%76.9%
Swing/Pivot (n=4)75.0%100.0%50.0%
Core Republican (n=27)13.0%14.8%27.8%
* Includes two Independents, Angus King of Maine and Bernie Sanders of Vermont, who caucus with Democrats.

While not a perfect overlay, these percentages tell a simple story: states that lean Democratic at the presidential level strongly tend to elect Democrats to statewide office, while states that lean Republican at the presidential level strongly tend to elect Republicans to statewide office. Thus, only five of 57 (8.8%) Democratic-state Senators and Governors are Republicans: the indomitable Senator Susan Collins of Maine, and the governors of Maryland, Massachusetts, New Hampshire and Vermont. By the same token, only 11 of 81 (13.6%) Republican-state Senators and Governors are Democrats: all four Senators from Arizona and Georgia; one Senator each from Montana, Ohio and West Virginia (political-gravity-defying Joe Manchin); and the governors of Kansas, Kentucky, Louisiana and North Carolina. In other words, only 16 of 138 (11.6%) Senators and Governors from these 46 states are from the “opposition” party. Curiously, in the four swing/pivot states, every governor and Senator except Senators Pat Toomey of Pennsylvania and Ron Johnson of Wisconsin—the pivot states—are Democrats. The House percentages are a bit murkier, reflecting Republican pockets in “Democratic” states and Democratic pockets in “Republican” states, but it is still the case that roughly ¾ of the House delegations from these 46 states “match” their state’s partisan lean; swing/pivot states are split literally down the middle: 22 Democrats and 22 Republicans.

Pick your cliché. “All politics is local.” Clearly, not any more, as elections become increasingly nationalized. “I vote the person, not the party.” Apparently no longer true, given how closely voting for president/vice president, Senate, governor and House track. “Vote the bums out.” Well, voters seem to prefer bums from their party to anyone from the other party. As I noted with gerrymandering, these trends, if they continue, may be far more damaging for our two-party democracy than for either political party.

Until next time…please stay safe and healthy…

2020 Elections Post-Mortem

On November 3, 2020, the United States ended a weeks-long electoral process. At stake was the presidency, control of the United States Senate (“Senate”) and House of Representatives (“House”), 11 governor’s mansions, and thousands of state and local offices. That day, I published “cheat sheets” to guide election viewers through state-level presidential returns, 35 Senate elections and the gubernatorial elections.

[Ed. note: This post, my 200th, is the longest I have written to date. It is fitting that a blog which found its data-driven footing in the wake of the 2016 elections would have its 200th entry address the aftermath of the 2020 elections, beyond mere repetition of the number “20.”]

As I write this on midnight EST on November 17, 2020, precisely two weeks after the elections concluded, these are the top-line results:

  • Only one governor’s mansion changed partisan hands: Republican Greg Gianforte won back the statehouse in Montana for the first time in 16 years. As of January 2021, Republicans will hold 27 governor’s mansions, and Democrats will hold 23.
  • Democrats basically held serve in state legislative races. For more details, please see here.

On balance, the 2020 elections affirmed the status quo: a nation roughly evenly split between Democrats and Republicans, though it remains possible the former could control, however narrowly, the White House, Senate and House for the first time since 2010.

Presidential election

Biden-Harris are closing on 79.0 million votes (50.9%), shattering the previous record of 69.5 million votes won by Democrat Barack Obama and Biden in 2008. Trump-Pence have just under 73.3 million votes (47.3%), ranking them second in history. Biden has now appeared on three of the four presidential tickets to receive the most votes, with Obama-Biden earning 65.9 million votes in 2012, edging out Clinton-Kaine in 2016 by about 65,000 votes. Third party candidates are receiving more than 2.8 million votes (1.8%), significantly lower than the 8.3 million votes (6.0%) such candidates received in 2016. Approximately 155.1 million votes have already been counted, with an estimated 4.1 million votes—mostly in California and New York—left to be counted. This ~159.2 million vote projection, or about 2/3 of all Americans eligible to vote, also shatters the previous record of 137.1 million votes set in 2016.

Biden-Harris’ 3.6 percentage point (“point”) margin is a 1.5-point increase from 2016, and 0.3-point decrease from 2012, making it the third consecutive presidential election in which the Democratic ticket won the national popular vote by between two and four points; adding 22 million voters did not fundamentally alter the partisan electoral divide. Based on my Electoral College model, a Biden-Harris win of 3.6 points equates to 296 EV, nearly the 306 EV they received; for a Republican ticket, this equates to 327 EV.

How did Biden-Harris win the Electoral College?

Table 1: 2020 and 2016 Presidential Election Results by State, Ranked from Highest to Lowest Biden-Harris Margin

StateEVWinnerClinton-Kaine MarginBiden-Harris MarginDelta
Rhode Island4Biden15.520.85.2
New Jersey14Biden16.915.5-1.4
New York29Biden22.513.7-8.8
New Mexico5Biden8.210.82.6
Maine4Biden (3)
New Hampshire4Biden0.47.47.0
North Carolina15Trump-3.7-1.42.3
South Carolina9Trump-20.4-11.78.7
Nebraska5Trump (4)-17.8-19.2-1.4
South Dakota3Trump-29.8-26.23.6
North Dakota3Trump-35.7-33.42.4
West Virginia5Trump-41.7-39.02.7
Average  Trump+3.6Trump+0.8D+2.8

As Table 1 reveals, Biden-Harris won 25 states and the District of Columbia (“DC”) by an average of 17.4 points, while Trump-Pence won 25 states by an average of 19.8 points; medians are 14.6—reflecting the 86.8-point margin in DC—and 18.6, respectively. Biden-Harris won seven states and DC totaling 97 EV by 20 or more points, while Trump-Pence won 11 states totaling 65 EV by that margin.

Biden-Harris won 19 states, DC and the 2nd Congressional district in Nebraska by at least 6.0 points, for a total of 228 EV. Add Nevada (6) and Michigan (16), which the Democratic ticket won by ~2.5 points, below their national margin, and the total increases to 250 EV.

At around 10:30 am EST on Saturday, November 7, the major news networks declared Biden-Harris the projected winner in Pennsylvania—and its 20 EV put Biden-Harris over the total of 270 needed to win the presidency. It also makes Pennsylvania—the state in which I was born—the “tipping point” state, as it puts Biden-Harris over 270 EV when states are ranked from most to least Democratic. But the margin stands at just 1.0 points, or just 68,903 votes; Biden-Harris also won Wisconsin (0.6 points), Arizona and Georgia (0.3 points each) by similarly small margins. The Democratic ticket has a total winning margin of 104,025 votes in these four states.

In the 25 states, plus DC, won by the Democratic ticket, the average increase in margin from 2016 was 3.4 points, while in states won by the Republican ticket the average increase was 2.1 points; overall, the average margin shift was 2.8 points. In the five states which switched from Republican to Democratic, the average increase was 3.0 points, led by a 3.8-point increase in Arizona and a 5.4-point increase in Georgia. While Biden-Harris lost North Carolina by 1.4 points and Texas by 5.7 points, they improved the margin by 2.3 and 3.3 points, respectively.

However, while Biden-Harris improved on the 2016 margins by an average 3.7 points in these four southeastern/southwestern states—states I suggested were fertile ground for Democrats—they basically held serve in Iowa (D+1.2) and Ohio (no change), while falling further behind in Florida (D-2.2); I will not speculate what role undelivered ballots in Miami-Dade County played in the latter state. This should not be surprising, as these were perhaps the most disappointing states for Democrats during the otherwise “blue wave” 2018 midterm elections.

In 2016, Trump-Pence won 306 EV by winning six states Obama-Biden won in 2012: the aforementioned Florida, Iowa and Ohio, plus Michigan, Pennsylvania and Wisconsin. The latter were decided by a combined 77,736 votes; Clinton-Kaine also lost Georgia by 211,141 votes and Arizona by 91,234 votes. In 2020, as Table 2 shows, Biden-Harris won the former three states—more than enough to give them an Electoral College victory—by a combined 233,945 votes: a shift of 311,681 votes, or just 0.2% of all votes cast. But the Democratic ticket also increased their margin in Arizona by 101,691 votes and in Georgia by a remarkable 226,296 votes.

Table 2: Changes in Margin from 2016 to 2020 in Five Key States

State2016 Dem Margin2020 Dem MarginIncrease, 2016-20

Overall, across these five states, the margin swung toward the Democratic ticket by about 640,000 votes, which is still less than 1% of all votes cast. But we can get even more granular than that. Early in 2017, I observed that in the three states that swung the 2016 election to Trump-Pence, the Clinton-Kaine ticket did about as well in the Democratic core counties—the urban centers of Detroit, Milwaukee/Madison and Philadelphia/Pittsburgh—as Obama-Biden had in 2012. What changed was a massive increase in Republican turnout in the other, more rural counties of those states. I ultimately concluded this resulted from a split between white voters with a college degree (more Democratic suburban/urban) and without a college degree (more Republican rural).

Table 3: Changes in Margin from 2016 to 2020 in Pennsylvania Counties

County2016 D Margin2020 D MarginIncrease, 2016-20
Phila Suburbs   
Major Urban   
All Other Counties-816,051-826,874-10,283

Table 3 shows just how this split played out in 2020, using Pennsylvania as an example. Compared to 2016, the margins for the Democratic ticket increased only at 21,000 votes in the heavily urban Democratic counties of Allegheny (Pittsburgh) and Philadelphia. And the 61 counties outside these two counties, excepting the four-county ring around Philadelphia, also held serve for the Republican ticket; Erie and Northampton Counties switched, barely, from Trump-Pence to Biden-Harris. In fact, the two parties may have reach voted saturation in these two areas. But those four suburban Philadelphia counties, swung even further toward the Democratic ticket, from a margin of 188,353 votes to nearly 291,422 votes, for a total increase of 103,069 votes, nearly the entire swing from 2016 to 2020.

What about the polling?

With most of the vote counted, Biden-Harris lead Trump-Pence nationally by 3.6 points, which is 4.6 points lower than my final weighted-adjusted polling average (“WAPA”) of 8.2 points.

For my final post tracking national and state polling of the 2020 presidential election, I estimated the probability Biden-Harris would win a given state. In 24 states/DC totaling 279 EV, the probability was at least 94.7%; Biden-Harris won all of them. In 20 states totaling 126 EV, the probability was 1.3% or less; Trump-Pence won all them. The remaining seven states were:

  • Florida (80.1%), which Biden-Harris lost
  • Arizona (77.5%), which Biden-Harris won
  • North Carolina (69.0%), which Biden-Harris lost
  • Georgia (56.4%), which Biden-Harris won
  • Ohio (39.1%), Iowa (37.0%) and Texas (28.4%), each of which Trump-Pence won

Florida and North Carolina were the only “misses,” though it should be noted Trump-Pence still had a non-trivial 19.9% and 31.0% chance, respectively, to win those states. Further, my final back-of-the-envelope EV estimate was 348.5 for Biden-Harris—subtracting the 44 combined EV of Florida and North Carolina essentially gets you to 306. The latter value is also very close to the 297.5 EV I estimated Biden-Harris would receive if all polls overestimated Democratic strength by 3.0 points.

Along those lines, my 2020 election cheat sheets included a projected Democratic-minus-Republican margin (“JBWM”), which adjusts final WAPA for undecided votes, along with recent polling errors in selected states. Compared to the final margins/polling averages (“538”), JBWM margins were about 1.2 points more Republican.

Even so, as Table 4 shows, the JBWM margins were, on average, 3.4 points more Democratic than the final margins, and the 538 margins were 4.6 points more Democratic. When the direction of the difference is ignored, meanwhile, the differences between the two method vanish: an average absolute difference of 4.5 from JBWM margins compared to 4.8 for 538.

However, this overall difference masks a stark partisan difference: the mean JBWM difference was only 1.1 points more Democratic in states/DC won by Biden-Harris, while it was 5.9 points more Democratic in states won by Trump-Pence. The correlation between the Biden-Harris margin and the JBWM difference is 0.73, meaning the more Republican the state, the better Trump-Pence did relative to the final polling. In short, pollsters continue to undercount “Trump Republicans” in the most Republican states.

Table 4: 2020 Presidential Election Results by State, Ranked by Difference from JBWM Democratic-Republican Margin “Projection”

StateEVWinnerJBWM ProjectionBiden-Harris MarginDelta
West Virginia5Trump-20.4-39.0-18.6
New York29Biden28.313.7-14.6
South Dakota3Trump-15.6-26.2-10.6
North Dakota3Trump-23.2-33.3-10.1
New Jersey14Biden19.515.5-4.0
Maine4Biden (3)12.58.7-3.8
South Carolina9Trump-8.9-11.7-2.8
New Hampshire4Biden8.97.4-1.5
Nebraska5Biden (4)-17.8-19.2-1.4
New Mexico5Biden12.010.8-1.2
North Carolina15Trump-1.1-1.4-0.3
Rhode Island4Biden19.020.71.7
Average  Biden+2.6Trump+0.8D-3.4

To again get more granular, Table 5 lists the pollsters who assessed the national popular vote at least five times since January 1, 2019, sorted by distance from the actual national margin of 3.6%. Margins are weighted for time, but not adjusted for partisan “bias.”

Table 5: Top 2020 Presidential Election Pollsters, Final WAPA National Margin

Pollster538 RatingFinal MarginDelta
NORC (AllAdults only)C+11.3-7.7
USC DornsifeB/C10.4-6.8
Quinnipiac UniversityB+10.4-6.8
NBC News/Wall Street JournalA-10.1-6.5
Global Strategy Group/GBAO (Navigator Res)C+9.9-6.3
Data for ProgressB-9.8-6.2
Redfield & Wilton StrategiesC+9.6-6.0
ABC News/Washington PostA+9.2-5.6
Marist CollegeA+9.1-5.5
Echelon InsightsC+8.8-5.2
Change ResearchC-8.3-4.7
Fox NewsA-8.3-4.7
Research Co.B-7.8-4.2
Morning ConsultB/C7.6-4.0
Monmouth UniversityA+7.4-3.8
Firehouse Strategies/OptimusB/C7.4-3.8
RMG ResearchB/C7.1-3.5
Harris XC6.5-2.9
Suffolk UniversityA6.2-2.6
Emerson CollegeA-3.8-0.2
Rasmussen Reports/Pulse Opinion ResearchC+3.20.4

           * John Zogby Strategies/EMI Solutions, Zogby Analytics, Zogby Interactive/JV Analytics

These 32 pollsters accounted for 556 (80.6%) of the 690 polls conducted. On average, they estimated Biden-Harris would win the national popular vote by 8.2 points, identical to my final WAPA; the average miss was 4.5 points in favor of Biden-Harris. There was only minimal difference by pollster quality: the 11 pollsters with a rating of B or better missed by an average of 4.2 points, while the 21 pollsters with a rating of B- or lower missed by an average of 4.7 points. That said, three of the four pollsters who came closest to the final national margin—Zogby, Rasmussen and Civiqs—had ratings of B/C or C+; the fourth was Emerson College, rated A-. At the other end of the spectrum are seven pollsters who anticipated a double-digit national popular vote win for Biden-Harris: low-rated Opinium, NORC (who polled adults, not registered/likely voters), CNN/SSRS, Qriously and USC Dornsife; and high-rated Quinnipiac University and NBC News/Wall Street Journal.

Overall, though, the polling captured the broad contours of the 2020 presidential election—if not the precise margins—fairly well, with JBWM and actual Democratic margins correlated a near-perfect 0.99; the order of states from most to least Democratic was accurately predicted. It forecast a solid, if not spectacular win by Biden-Harris in the national popular vote, a restoration of the upper Midwestern “blue wall,” and continued Democratic gains in southeastern/southwestern states such as Arizona, Georgia, North Carolina and Texas, even as Florida, Iowa and Ohio become more Republican.

One final note: it is exceedingly difficult to beat an elected incumbent president. Since 1952, it had happened only twice (1980, 1992) in eight chances prior to 2020[1]; Biden-Harris beat those 1:3 odds convincingly.

Senate elections

Democrats entered 2020 needing to flip a net four seats—or three seats plus the White House—to regain the majority for the first time since 2014. As Vice-President-elect, Kamala Harris breaks a 50-50 tie.

Table 6: 2020 Senate Election Results by State, Ranked from Highest to Lowest Democratic Margin, Compared to Pre-Election “Fundamentals”

StateWinnerFundamentalsFinal Dem MarginDelta
Rhode IslandReed24.433.08.6
New JerseyBooker18.415.8-2.6
New HampshireShaheen6.515.79.2
New MexicoLujan8.56.1-2.4
Georgia Special???-8.0-1.07.0
North CarolinaTillis-6.4-1.74.7
South CarolinaGraham-16.1-10.35.8
South DakotaRounds-26.2-31.5-5.3
West VirginiaCapito-35.9-43.3-7.4
AverageD+1 to 3GOP+8.9GOP+7.0D+1.9

Table 1 summarizes these elections; for the Georgia special election and Louisiana, margins are for all Democrats and all Republicans. Democrats John Hickenlooper and Mark Kelly defeated Republican incumbents in Colorado (Cory Gardner) and Arizona (Martha McSally), respectively, while Republican Tommy Tuberville defeated Democratic incumbent Doug Jones in Alabama. This leaves Democrats two seats shy of 50-50, pending the January 5 runoff elections in Georgia. Incumbent Republican David Perdue edged Ossoff on November 3 by 1.7 points, but fell 0.3 points short of the 50.0% needed to win outright. In the special election necessitated by the retirement of Republican Johnny Isaakson in December 2019, Warnock (32.9%) led incumbent Republican Kelly Loeffler (25.9%) by 7.0 points in the all-candidate “jungle primary;” overall, Republican candidates earned 49.4% of the vote and Democratic candidates earned 48.4%, with 2.2% split between a handful of third-party candidates.

When I took a “wicked early” look at these elections, I assessed the Democrat’s chance in each election using their “fundamentals,” or the sum of the state’s partisan lean (calculated using my 3W-RDM), the Democratic margin on the generic ballot and incumbency advantage.[2] For Table 6, the generic ballot is the difference in the percentages of the total vote for all Democratic House candidates and for all Republican House candidates; Democrats are ahead by 2.0 points.

On average, Democrats overperformed “expected” margins by 1.9 points. In the 13 elections won by Democrats, the overperformance was 2.5 points, while in the 20 elections won by Republicans, the overperformance was just 0.9 points; Democrats overperformed in the two Georgia Senate races by 7.0 and 8.3 points, confirming how rapidly it is moving toward swing-state status. The biggest Democratic overperformance—fully 10.7 points—was in Arizona, which in 2021 will have two Democratic Senators (both of whom beat McSally) for the first time since 1953. Other Senate elections in which the Democratic candidate overperformed by at least 9.0 points were New Hampshire, and three states where Democrats fell short in their attempt to win back a Republican-held seat: Montana, Kansas and Kentucky.

On the flip side, setting aside a 15.1-point underperfomance in Nebraska, the biggest Republican overperformance was in Maine, where incumbent Susan Collins, first elected in 1996, “should” have lost by 5.5 points. Instead, she won by 8.9 points; this is a 28-point decline from 2014, when Collins won by 37 points. Pending the results of the Georgia runoff elections, Maine is the only state in 2020 to have a Democratic presidential victory and a Republican Senate victory, with a gap of 17.6 points. It will be interesting to see whether Collins adjusts her voting in the next Senate. Other large Democratic underperformances, finally, took place in Michigan, where first-term Democratic Senator Gary Peters beat Republican John James by only 1.5 points and in West Virginia, which grows more Republican every year.

On the whole, though, expected and actual margins aligned nearly perfectly, with a 0.94 correlation.

What about the polling?

As with the presidential election, the final polling averages/projected margins were far less accurate, as Table 7 shows; I did not calculate a projected final margin for the Louisiana Senate election.

Table 7: 2020 Senate Election Results by State, Ranked by Difference from JBWM Democratic-Republican Margin “Projection”

StateWinnerJBWM ProjectionDemocratic MarginDelta
West VirginiaCapito-20.6-43.3-22.7
South DakotaRounds-19.9-31.5-11.6
New JerseyBooker24.615.8-8.8
South CarolinaGraham-4.7-10.3-5.6
New MexicoLujan10.06.1-3.9
North CarolinaTillis1.1-1.7-2.8
New HampshireShaheen14.415.71.3
Georgia Special???-3.9-1.02.9
Rhode IslandReed29.633.03.4
AverageDem+1 to 3GOP+0.6GOP+6.4D-5.8

The polling may have been within historic parameters for the presidential election, but it was far worse in the Senate elections, with the JBWM margins overestimating Democratic margins by an average of 5.8 points, almost exactly the 6.0 points by which 538 margins erred on average; ignoring direction, the average misses are 6.3 and 7.0 points, respectively. That said, the correlation between the actual and projected Democratic margins was 0.97, meaning the polling correctly forecast the order of Senate elections from most to least Democratic.

These overall averages again mask substantial partisan differences. In the 13 states where the Democratic nominee won, the average miss was a historically-reasonable -2.9 points, but in the 19 states (excluding Louisiana) where the Republican nominee won, the average miss was an astounding -8.3 points. Put another way, in the 15 states Trump-Pence won by at least 10 points which also held a Senate election, the average Senate miss was -8.9 points, while it was -3.3 points in all other states. Somewhat reassuringly, in the five states whose presidential margin was within five points also holding a Senate election (Arizona, Georgia, Michigan, North Carolina), the miss was only -2.2 points. Overall, the correlation between the Biden-Harris margin and the JBWM margin error was 0.57, confirming the idea pollsters systematically undercounted Republican support in the most Republican states.

My back-of-the-envelope estimate was a net gain of five Democratic seats in the Senate, with at least a 77% chance Democrats would regain control; these values dropped to 30% and either two or three seats with the assumption all polls systematically overestimated Democratic strength by three points. Democrats will ultimately net between one and three seats, corresponding more with the latter assumption. I estimate the probability Democrats win both Georgia Senate runoff elections—and thus the Senate—is between 25 and 50%, depending on the degree of ticket-splitting.

From a purely mathematical perspective, the largest Democratic underperformances occurred in the Senate elections in West Virginia, Wyoming, South Dakota and Nebraska: four extremely Republican states. But from a strategic perspective, the most disappointing elections were in Maine (-12.2) and North Carolina (-2.8), where incumbent Republican Thom Tillis narrowly held off a challenge from Democrat Cal Cunningham, who may have been hurt by a sexting scandal; given the narrowness of his victory (1.7 points) and the increasingly swing status of North Carolina, Tillis’ voting patterns also merit watching. These were the two states besides Arizona (98.1%) and Colorado (99.5%) in which I estimated the Democratic nominee had at least an 85% chance to defeat a Republican incumbent; I also thought Democrat Theresa Greenfield was roughly even money to defeat incumbent Republican Joni Ernst, despite projecting a final margin of 3.6 points for Ernst; the latter won by 6.6 points.

There were four additional Senate elections—in Alaska, Kansas (open seat), Montana and South Carolina—where I estimated the probability of a Democratic flip was between 11.7 and 26.4%. In a sign of how good these elections were for Republicans, their nominees won all four elections by an average of 11.3 points, a mean 7.5 points more Republican than projected. In fairness, these states tilted an average 19.2 points more Republican than the nation as a whole coming into the 2020 elections. A similar story can be told in Texas, which tilted 15.3 points more Republican, but where Democrat M.J. Hegar “only” lost by 9.8 points to incumbent Republican John Cornyn, beating expectations by 0.6 points.

Put simply, assuming a loss in Alabama, Democratic hopes of winning back control of the Senate relied on flipping two Senate seats in Democratic states, then winning at least two more seats in states ranging from somewhat Republican—Iowa, North Carolina, Arizona, Georgia—to extremely Republican—Alaska, Kansas, Montana, South Carolina and Texas—all while Trump sought reelection. To date, Democrats have only flipped seats in Colorado (D+2.2) and Arizona (D-9.7) while winning back the Vice-Presidency, losing tough elections in Iowa, Maine and North Carolina, while never really being in contention anywhere else. Senate control now rests on Democrats winning two Senate runoff elections in a nominally Republican state (D-9.6), but one where Biden-Harris won, improving on Clinton-Kaine’s by 5.4 points.

Gubernatorial elections

Unlike those for the White House and Senate, there was very little drama in these elections. Two Democratic incumbents—John Carney of Delaware and Jay Inslee of Washington—were expected to win easily; they won by margins of 20.9 and 13.6 points, respectively. Six Republican incumbents—Eric Holcomb of Indiana, Mike Parson of Missouri, Chris Sununu of New Hampshire, Doug Burgum of North Dakota, Phil Scott of Vermont and Jim Justice of West Virginia—as well as Republican Spencer Cox of Utah were expected to win easily, though I projected Parson to win by “only” 8.0 points (he won by 16.6 points). They won their elections by an average margin of 31.6 points!

The only possible drama was in Montana, where Republican Gianforte and Democrat Mike Cooney vied to win the governor’s mansion being vacated by Democrat Bullock, and North Carolina, where Democratic Governor Roy Cooper—who won extremely narrowly in 2016—faced Republican Dan Forest. Gianforte defeated Cooney by 12.4 points, easily exceeding a projected 4.5 points, while Cooper won by 4.5 points, not the projected 10.4 points. Still, my global projection was correct: a net gain of one governor’s mansion by the Republicans, giving them a 27-23 majority; this an overall net gain of seven governor’s mansions by the Democrats since 2016.

In these elections, Republicans strongly overperformed fundamentals (7.1 points) and JBWM projections (7.6 points). However, expected values were strongly skewed by Scott’s 41.1-point victory in extremely-Democratic Vermont (D+27.7) and Sununu’s 31.8-point victory in swing New Hampshire (D+0.1); exclude those two margins and DEMOCRATS overperformed expectations by 1.0 points—with Democrat Ben Salango exceeding what were admittedly very low expectations by 8.5 points. Meanwhile, in the four states with governor’s races won by Biden-Harris, Democratic gubernatorial nominees finished an average 8.9 points lower than projected, while in the seven states won by Trump-Pence, they finished an average 6.8 points worse than expected. Once again, the extreme disparity in presidential/Senate and gubernatorial voting in New Hampshire and Vermont—two of three states in solidly-Democratic New England, along with Massachusetts (Charlie Baker), to have very popular Republican governors. In fact, gubernatorial elections are among the only ones in which ticket-splitting is still relatively common: Biden-Harris won six states with a Republican governor,[3] while Trump-Pence won five states with a Democratic governor.[4]

House elections

A wide range of forecasters expected Democrats to net between five and 10 House seats[5]. I was highly dubious of this, to be honest, given the likelihood the margin for Democrats in the total national House vote would decline from the 8.6-point margin they earned in 2018; it would also be higher than the 1.1 points by which they lost in 2016, when they still managed to net six seats. However, because I was not closely tracking House races, I said nothing about my doubts.

According to the Cook House vote tracker, Democrats had earned more than 75.1 million House votes (50.1%), Republicans had earned just under 72.1 million votes (48.0%), with the nearly 2.2 million votes (1.8%) going to third-party candidates. A total of 150.0 million votes have been counted, 5.1 million less than those cast in the presidential election. The 2.0-point margin by which Democrats are winning the House vote—just under 3.1 million votes—is also lower than the 3.6 points, and 5.6 million votes by which Biden-Harris currently lead Trump-Pence. It is also much lower than the 9.7-million Democratic vote margin in 2018, albeit with 36.3 million more votes cast in 2020, reinforcing the conclusion a few million Republican-leaning voters “balanced” a vote for Biden-Harris with Republican votes elsewhere…or simply chose not to vote in down-ballot elections.

In the races that have already called, Republicans have gained 11 seats held by Democrats (two each in California and Florida, one each in Iowa, Minnesota, New Mexico, New York, Oklahoma, South Carolina and Utah), while Democrats have gained three seats held by Republicans (two in North Carolina, one in Georgia). This gives Democrats 221 seats, three more than needed for the majority, and Republicans 208 seats. Of the six seats yet to be called, Democrats currently hold four, with freshman Democrat Tom Malinowski leading by ~5,000 votes in New Jersey’s 7th Congressional District (“CD”). Giving that seat to the Democrats—and giving Republicans their open seat in New York’s 2nd CD—increases the totals to 222 Democrats and 209 Republicans.

That leaves four seats truly in doubt:

  • California’s 21st CD, where incumbent Democrat T.J. Cox trails Republican David Valadao, in a 2018 rematch, by 2,065 votes.
  • California’s 25th CD, where Democrat Christy Smith is within 104 votes of unseating Republican Mike Garcia, who won a special election in May 2020 after first-term Democrat Katie Hill resigned.
  • Iowa’s 2nd CD, where Democrat Dave Loebsack did not seek reelection; Republican Mariannette Miller-Meeks leads Democrat Rita Hart by only 47 votes!
  • New York’s 22nd CD, where Republican Claudia Tenney’s lead over incumbent Democrat Anthony Brindisi continues to shrink as New York votes are slowly counted.

Democrats will thus lose a net 8-12 seats compared to the 234-201 margin they had after the 2018 elections. This is a bad result for the Democrats, right?

Well, no…it suggests that polling-based expectations were flawed, because the fundamentals always pointed toward a net loss of House seats for the Democrats. Moreover, the comparison should be to 2016, because that is the last election in which Trump appeared on the ballot.

Following the 2016 elections, Republicans had a 241-194 House majority. Democrats were convinced, wrongly I thought, that gerrymandering by Republican legislators and governors would keep them in the minority for the foreseeable future. Looking ahead to the 2018 midterm elections, knowing Democrats needed to net 24 seats to regain the majority, I looked at all House elections from 1968 to 2016, and I noticed that what “predicted” net change in seats from one election to the next was not the national margin in a given election, but the change in that margin from the previous election. Figure 1 helps to illustrate this.

Figure 1:

In 2018, Democrats net a surprisingly-high 41 House seats, 17 more than they needed, most by narrow margins. It is then reasonable to expect that even a small decline in the Democratic share of the total national House vote would allow Republicans to “claw back” some of these seats Democrats currently lead the total national House vote by 2.0 points, fully 6.6-point decrease f 2018. Entering this value into the OLS regression shown in Figure 1 yields an estimated Democratic loss of 22.4 seats.

In other words, while Democrats expected to gain seats—based on what we now know was polling that underestimated Republican margins by 3-7 points—they should actually have been bracing themselves for a possible loss of the House itself. Instead, they “only” lost between eight and 12 seats, meaning they did far better than history would have suggested. Moreover, Democrats have net between 29 and 33 seats since 2016, earning control of the House in back-to-back elections for the first time since 2006-2008, something that seemed nearly impossible early in 2017.


Both Democrats and Republicans can find 2020 election results to celebrate.

Democrats won back the White House after just four years (beating 1:3 odds to defeat an incumbent), rebuilding their upper-Midwestern blue wall while expanding into the southeast and southwest; no Democratic presidential nominee has won both Arizona and Georgia since 1948. They also maintained control of the House of Representatives and made gains in the Senate; with two more wins in Georgia in January 2021, they regain control of the Senate as well. Democrats have not controlled both the White House and House since 2010.

Republicans, even as they lost the White House, gained as many as 12 seats in the House and staved off losing control of the Senate until January 2021 at the earliest. They net one governor’s mansion, giving them a 27-23 majority, and held their own in state legislative elections. Once again, Trump’s name on the ballot encouraged many more exurban and rural voters to vote than expected, ironically helping all Republicans but himself and his running mate.

Fans of bipartisan “balance” can also celebrate 11 states seeing different parties win their state’s electoral votes and serving as governor. Moreover, a record-smashing 155.1 million—and counting—Americans cast a ballot for president, which equates to two in three of all adults eligible to vote.

Finally, the polls erred substantially in favor of Republicans, with a miss of around 3.5 points compared to my final projections and 4.7 points relative to those from 538. Republicans fared even better in Senate and gubernatorial elections, beating final projections by around six points in the former and nearly eight points in the latter. These values mask a partisan split, with polls far more accurate for Democratic candidates than Republican ones. In the end, though, polls were far less accurate—in this Trump-led cycle at least—than simply considering a state’s recent partisan lean, the national partisan environment and incumbency. These fundamentals remain extremely predictive, at least relatively.

Until next time…please stay safe and healthy…

[1] 1956, 1972, 1980, 1984, 1992, 1996, 2004, 2012

[2] Democratic full-term incumbents=4.4, Democratic partial-term incumbents=2.2, non-incumbent=0, Republican partial-term incumbents=–0.4, -0.6, -1.6; Republican full-term incumbents=-2.4

[3] Arizona, Georgia, Maryland, Massachusetts, New Hampshire, Vermont

[4] Kansas, Kentucky, Louisiana, Montana, North Carolina

[5] The Cook Political Report hedged a bit, labeling 229 seats at least Lean Democrat, 179 seats at least Lean Republican, and 27 seats Toss-up. Of the Toss-ups, nine are held by Democrats, 17 by Republicans, and one by Justin Amash of Michigan, who switched from Republican to Independent in July 2019.

Your 2020 Election Cheat Sheets

Election Day 2020 has finally arrived. More accurately, the end of election season comes today, as over 100 million Americans have already voted. To help guide you through the coming hours of media coverage, I have attached two PDFs.

The first one allows you to track the results of the presidential election. For my last update and to understand how I aggregate all polls assessing Democratic presidential nominee Joseph R. Biden, Jr. versus Republican President Donald J. Trump, please see here.

The second one allows you to track, the results of the 36 Senatorial and 11 gubernatorial elections. In the column headed “538CL,” I list the final projected Senate election margins using their “Classic” methodology. The analysts at 538 did not track gubernatorial elections this year. For my last update, see here.

Names of incumbents are underlined in italics, while, in open seats, the candidate of the incumbent’s party is in italics. Values highlighted in blue are projected Democratic gains, and values highlighted in red are projected Republican gains.

In both trackers, the column headed “JBWM” list my my best estimate of the final margins in each election, not the polling averages. In most states, this is essentially the same as the final polling average. Since my last update, I made two algorithm changes. First, I weight all poll conducted entirely after the final presidential debate on October 22 six times higher. Second, I halve the weight of any poll with a one-day field date.

However, in the 13 key Electoral College states of Arizona, Florida, Georgia, Iowa, Michigan, Minnesota, Nevada, New Hampshire, North Carolina, Ohio, Pennsylvania, Texas and Wisconsin, and in the key Senate battlegrounds of Alaska, Arizona, Colorado, Georgia, Iowa, Kansas, Maine, Michigan, Minnesota, Mississippi, Montana, North Carolina and Texas, I began by assigning between 0.5 and 3.0 percent of the total vote to third party candidates, essentially eyeballing their polling percentages and cutting them in half. I then adjusted the final polling margin, for states for which I had this information, by the average 2016-2018 miss, as calculated by Dave Wasserman. Finally, I divided the remaining–usually minimal–undecided vote based on the relative Democratic or Republican lean of the state and the early vote count as a share of the 2016 vote totals. Put simply, in strong Democratic states with high turnout, I gave two-thirds of the undecideds to Biden, in strong Republican states with lower turnout I gave two-thirds of the undecideds to Trump, and where the two metrics diverged, I split them evenly.

With that in mind, here are some general observations.

  1. Maine and Nebraska assign two Electoral Votes (“EV”) to the statewide winner and one each to the winner of the state’s two and three Congressional districts (“CD”), respectively. I did not analyze polling data from the 2nd CD of Nebraska or the 2nd CD of Maine. While I expect Biden to win the former (and the 1st CD of Maine), I have no clear sense of who will win the latter; Trump will easily win the other two CD in Nebraska.
  2. My final “product of EV probabilities” sums are 348.5 using all polls conducted since January 1, 2019, and 350.6 using only polls conducted since the national party conventions concluded on August 28. With a systemic three-point polling error favoring Republicans, the EV total drops to 297.5, and with a systemic pro-Democratic error the EV total jumps to 391.2
  3. In my 2020 presidential election cheat sheet, Biden wins a total of 290 EV in states where I project him to win by at least 2.2 points, including NE-2; the latter state is Pennsylvania, with 20 EV–losing it drops Biden to exatly the 270 he needs to win. Note that I “award” North Carolina to Trump, while 538 has Biden slightly favored there. I am far less certain of three states whose 83 total EV–Florida, Georgia and Texas–I “award” to Biden by very narrow margins; 538 has Trump slightly favored in Texas. Honestly, Biden could win all four of these states, Trump could win all four, or any combination in between. Thus, by my calculations, Biden could win anywhere from 290 to 373 EV–very close to my six-point polling error spread.
  4. Recall that there are two Senate elections in Georgia, one scheduled between Democrat Jon Ossoff and Republican incumbent David Perdue, and one being defended by incumbent Republican Kelly Loeffler in which all candidates run in the same election. In the former, I “award” the win to Ossoff, but if neither candidate reaches 50%–and Libertarian Shane Hazel routinely earns ~3% in public polling–there will be a runoff election on January 5, 2021. In the latter race, it is a near certainty Democrat Raphael Warnock will advance to a runoff election on January 5, probably–but not certainly–against Loeffler. As of now, Warnock is the strong favorite to win that election.
  5. Louisiana also has a “jungle” primary for Senate, with a runoff between incumbent Republican Bill Cassidy (if he does not reach 50% today) and Democrat Adrian Perkins a near-certainty.
  6. I line up exactly with 538 on Senate races, though the Senate race in Iowa is quite close. We both anticipate the next Senate to have 50 Democrats, plus two Independents who caucus with them, and 48 Republicans.
  7. However–keep an eye on Montana. Democratic Governor Steve Bullock is a very slight underdog against incumbent Republican Steve Daines, but could also easily eke out a narrow win. And the only remotely competitive governor’s race–an open seat battle between Democratic Lieutenant Governor Mike Cooney versus House Member Republican Greg Gianforte–is being held there as well.

And that is it.

Time to prepare a batch of blue lagoons, ready my bowl of blue and white M&M’s and settle in for a long night…or week.

Until next time…please stay safe, and if you have not done so already, please VOTE!

Quinnipiac University and Emerson College: Mirror-image pollsters?

In three earlier posts—most recently here—I analyzed all polls conducted by Emerson College (“Emerson”) of 2020 presidential, senatorial and gubernatorial elections. I found that they had a clear bias towards the Republican candidate, on average, compared to all other polls of the same election.

As I continue to analyze polls of the presidential election between former Vice President Joseph R. Biden, Jr. and President Donald J. Trump, as well as this year’s 35 Senate and 11 gubernatorial elections, I have observed the opposite mathematical bias for Quinnipiac University (“Quinnipiac”) polls.

In fact, as we will see, the two polling organizations nearly mirror each other in their mathematical bias.


Let us begin with the national race between Democrat Biden and Republican Trump. Using all 632 publicly-available polls released since January 1, 2019, I calculated a weighted-adjusted polling average (WAPA) of 8.3. That is, adjusting for time (with polls conducted after August 29 weighted and additional 1.5 times higher and polls conducted since September 29 3.0 times higher), pollster quality and partisan lean, Biden leads Trump by a little over eight points nationally. Emerson has an A- rating, and a historic lean of 0.3 points Democratic, while Quinnipiac has a B+ rating, and a historic lean of 0.2 points Democratic.

Table 1: State-level 2020 presidential election polling averages by Emerson College and Quinnipiac University compared to all other pollsters in the same state

StateQuinnipiac  Emerson 
California   29.328.60.8
Iowa   -0.40.5-0.9
Massachusetts   36.934.32.6
Montana   -12.1-6.1-5.9
Nevada   -0.16.0-6.1
New Hampshire   7.88.1-0.3
North Carolina   0.92.1-1.2
South Carolina-4.2-7.12.8   
AVERAGE All States3.5  -0.5
AVERAGE Ohio, Pennsylvania, Texas1.9  -0.7

However, using the same calculation method—except for ignoring partisan lean—the 20 Emerson polls conducted by Emerson give Biden “only” a 3.7-point lead, which is 5.3 points more Republican than the average of the other 612 polls. At the same time, the 13 Quinnipiac polls give Biden a 9.9-point lead, which is 1.0 points more Democratic than the average of the other 619 polls. Put another way, Quinnipiac polls “see” a race that is 6.3 points more favorable to Biden than Emerson polls do, though both give Biden a solid lead.

While national polls are interesting—and plentiful—it is the Electoral College that determines who wins presidential elections. Table 1 compares state-level presidential polling averages by Emerson and Quinnipiac, in states where they have assessed the presidential election at least twice, to those calculated by all other pollsters in the state; positive values indicate a Democratic lead or pro-Democratic bias, and negative values indicate the opposite. Emerson has conducted one poll of the presidential election in Florida, Georgia, New Mexico, New Jersey and South Carolina; Quinnipiac has conducted one poll of the presidential election in Colorado, Connecticut, Iowa, Michigan, New Jersey, New York and Wisconsin.

In the 13 states where Emerson has assessed the 2020 presidential election, the average bias is only 0.5 points towards Trump, fully 4.8 points lower than its national bias toward Trump. By contrast, in the eight states where Quinnipiac has assessed this election—five of them in the south, the average bias is 3.5 points toward Biden, 2.5 points higher than its national bias toward Biden. The gap between the two polling organizations also narrows from 6.3 to 4.0 points at the state level.

Notably, while Quinnipiac has an average bias toward Biden in all eight states—ranging from more than five points in Georgia, Maine and Florida to around one point in Ohio and Texas—Emerson’s bias is evenly split across its 13 multiple-assessment states, ranging from nearly six points towards Trump in the western states of Montana and Nevada to between two and four points toward Biden in the disparate states of Arizona, Massachusetts (where Emerson College is located) and Michigan.

Curiously, Emerson and Quinnipiac have both assessed the 2020 presidential election in only three states—Ohio, Pennsylvania and Texas—multiple times since January 1, 2019. In these three states, the bias is relatively narrow: Trump +0.7 for Emerson and Biden +1.9 for Quinnipiac, for a gap of “only” 2.6 points.


Turning to other statewide elections in 2020, Table 2 compares Senate election polling averages by Emerson and Quinnipiac, in states where they have conducted such polls at least twice since January 1, 2020, to those calculated by all other pollsters in the state. Emerson has conducted one Senate election poll in Georgia, assessing both seats on the ballot this year, as well as in Arizona, Iowa, Michigan, Minnesota, New Hampshire and New Jersey; Quinnipiac has conducted one Senate election poll in Iowa and Michigan. For the “jungle primary” in which Georgia Republican Senator Kelly Loeffler seeks reelection, I analyze the difference between the total percentage for all Democratic candidates and the total percentage for all Republican candidates.

Table 2: 2020 Senate and gubernatorial election polling averages by Emerson College and Quinnipiac University compared to all other pollsters in the same election

StateQuinnipiac  Emerson  
Montana   -8.4-0.8-7.6
North Carolina   2.65.1-2.4
South Carolina0.0-2.82.8   
AVERAGE  3.3  -5.0

In a reverse of state-level presidential election polling, Quinnipiac has assessed six Senate elections multiple times—again focusing on the south, while Emerson has only assessed Senate elections in Montana and North Carolina more than once; no Senate election has been polled multiple times by both pollsters. Quinnipiac has an average 3.3-point bias toward Democratic Senate nominees, nearly identical to its 3.5-point state-level presidential election bias. By contrast, albeit only in two Republican-leaning states, Emerson has an average 5.0-point bias toward the Republican Senate nominees, nearly identical to their Trump bias nationally, and fully 4.5 points higher than their state-level bias toward Trump. Overall, and recognizing this is not an apples-to-apples comparison, Quinnipiac Senate election polls lean 8.3 points more Democratic than Emerson Senate election polls.

Quinnipiac has been especially Democratic-leaning in Georgia’s two Senate elections, with average pro-Democratic-nominee biases of 6.2 and 7.2 points, and in Maine, while they have shown minimal bias in Kentucky and Texas. As with the presidential election, meanwhile, Emerson has a whopping 7.6-point bias toward incumbent Montana Republican Senator Steve Daines in his race against Democratic Governor Steve Bullock; they are relatively closer to the mark in North Carolina, where Democrat Cal Cunningham has a small lead against incumbent Republican Thom Tillis.

Quinnipiac has conducted no gubernatorial election polls this year, while Emerson has conducted one poll in New Hampshire and multiple polls in Montana (6.5 points more Republican) and North Carolina (7.4 points more Republican), with a large average pro-Republican bias of 6.9 points!


Table 3 lists the average partisan biases for Emerson and Quinnipiac for each set of races.

Table 3: Average partisan biases in Emerson College and Quinnipiac University polls across multiple election categories


While Quinnipiac has had only a relatively small pro-Biden bias in national polls, they have had an overall lean of 2.6 points Democratic across all elections they have assessed multiple times. By contrast, while Emerson has been very close to the all-polls average in their state-level presidential election polling, they have had an overall lean of 4.4 points Republican across all elections they have assessed multiple times. Overall, Quinnipiac has leaned fully 7.0 points more Democratic than Emerson has.

I will not attempt to “explain” these relative partisan biases, though they almost certainly result from some combination of how the demographic distribution of the likely 2020 electorate is modeled, the fact Quinnipiac shifted to “likely voters” models more recently than Emerson did, how hard they “push” initially undecided voters to choose one candidate, and the relative partisan leanings of demographic categories within their respective samples.

I will say, though, that the final Democratic-minus-Republican margin will almost certainly be very close to the midpoint of the two polling averages plus one point Democratic—at least in elections assessed at least once by Emerson and by Quinnipiac.

Until next time…please stay safe and healthy…and if you have not already voted, please do so as soon as you can!

October 2020 update: Democratic control of the Senate looks increasingly likely

Democrats are poised to do extremely well when voting concludes on November 3, 2020—just 16 days from now; as I write this, more than 26.5 million votes have already been cast, which is 19% of the total 2016 turnout. They are a near-lock to continue to have a majority of members of the United States House of Representatives (“House”), and their presidential nominee, former Vice President Joseph R. Biden, Jr., is the clear favorite to win.

And then there is the United States Senate (“Senate”). Currently, there are 53 Republicans, 45 Democrats and 2 Independents who caucus with Democrats in the Senate. To regain control, Democrats must either win a net total of four Senate seats OR a net total of three Senate seats while winning back the presidency; as president of the Senate, Vice President Kamala Harris would break the 50-50 tie.

As of now, Democrats are favored to regain control of the Senate. This conclusion is based upon a political climate strongly favoring Democrats—they lead by 7.2 percentage points on the generic ballot[1]—and all publicly-available polls conducted since January 1, 2020.

Before continuing, here is the October 2020 lighthouse photograph in my Down East 2020 Maine Lighthouses wall calendar.


In a previous post, I detail how I calculate and combine…

  1. “Expected Vote” (how a generic Democrat would fare against a generic Republican given state partisan lean, incumbency and partisan climate) and
  2. My weighted-adjusted polling averages (“WAPA”), which average two versions of WAPA: one treating all polls from the same pollster as statistically independent and one calculating a time-weighted average for each pollster

…into a single projected Democratic-minus-Republican margin and the probability the Democrat wins. As of now, the latter accounts for at least 89% of the projected margin in the Senate races assessed with a publicly-available poll at least once in 2020; in the six states with no polling,[2] the Expected Value is the projected margin.

Table 1 reports two projected Democratic-minus-Republican margins and Democratic win percentages for this year’s 35 Senate elections: one using all polls conducted since January 1, 2020, and one using only polls conducted since the two national party conventions. I now weight all polls conducted after August 28 (the day the conventions ended) and before September 29 (the day of the first presidential debate) 1.5 times higher than previous polls, and I weight all polls conducted entirely after September 29 3.0 times higher. The table is sorted by likelihood the Democrat (or Independent Al Gross in Alaska) wins the election, based upon all 2020 polls.

Table 1: Projected 2020 Democratic minus Republican margins and likelihood of Democrat winning calculated two ways

StateCurrent PartyMargin since 1/1/2020Dem win%Margin since 8/29/2020Dem win %
Rhode IslandDEM29.4100.0%29.4100.0%
New JerseyDEM23.9100.0%24.3100.0%
New MexicoDEM10.799.8%9.999.7%
New HampshireDEM14.499.8%14.199.8%
North CarolinaGOP5.094.1%4.893.5%
South CarolinaGOP-3.116.9%-2.324.4%
South DakotaGOP-21.20.1%-21.20.1%
West VirginiaGOP-20.60.0%-20.60.0%

Georgia Republican Senator Kelly Loeffler, appointed by Governor Brian Kemp in December 2019 after Senator Johnny Isakson retired, is running for reelection in a “jungle” primary in which every candidate, regardless of party affiliation, appears on the November 3 ballot. If no candidate tops 50%, a runoff election between the top two vote-getters will take place on January 5, 2021. Republican House Member Doug Collins of Georgia is also running, as are Democrats Raphael Warnock, senior pastor of Ebenezer Baptist Church in Atlanta, Matt Lieberman, son of 2000 Democratic vice-presidential nominee Joe Lieberman, and former United States Attorney Ed Tarver. I calculate WAPA both for the all-candidate election on November 3—polls of which strongly imply either a Warnock-Loeffler or Warnock-Collins runoff—and hypothetical head-to-head matchups between the top two Republicans and the top three Democrats, combining them into a single “Democrat vs Republican” average as follows:

  1. Calculate averages, weighted by number of publicly-available 2020 polls, of the Democratic margins over Loeffler and Collins. Based on 11 total polls, Loeffler is about 3.6 points behind the top three Democrats, while Collins is behind 1.5 points based on nine total polls.
  2. Take the unweighted average of the Loeffler and Collins averages
  3. Calculate a final average “Democratic vs. Republican” margin, giving the head-to-head matchups twice the weight of the “all candidates” WAPA


Let us examine these 35 elections in groups.

Safe Democratic (10). Senators Edward Markey of Massachusetts, Jack Reed of Rhode Island, Richard Durbin of Illinois, Cory Booker of New Jersey, Chris Coons of Delaware, Jeff Merkley of Oregon, Mark Warner of Virginia and Jeanne Shaheen of New Hampshire should easily win reelection by double-digit margins, while in New Mexico’s open seat House Member Ben Ray Lujan is expected to beat meteorologist Mark Ronchetti by around 11 points. First-term Senator Tina Smith of Minnesota is now a clear favorite as well, with a final margin around nine points.

Likely Democratic (1). First-term Senators Gary Peters of Michigan is considered vulnerable because he represents the closest state in the 2016 presidential election. And when examining only the “polls are statistically independent” WAPA, Peters’ margin has dropped sharply from 9.6 points through the end of the conventions to 5.5 points since then. Nonetheless, I expect him to prevail over businessman John James by low-to-mid-single-digits.

Likely Democratic flips (4). Four incumbent Republican Senators—Cory Gardner of Colorado, Martha McSally of Arizona, Susan Collins of Maine and Thom Tillis of North Carolina—appear headed for defeat by single-digit margins; these margins changed little pre- and post-conventions, with McSally gaining 0.9 points and Collins losing 1.6 points. McSally and Gardner are the most likely to lose—by high single digits—to, respectively, former Governor John Hickenlooper and former astronaut Mark Kelly, husband of former Arizona House Member Gabrielle Giffords, who was shot and severely wounded in January 2011. Collins and Tillis, meanwhile, trail Maine Speaker of the House Sara Gideon and former North Carolina State Senator Cal Cunningham, respectively, by around five points.

Lean Democratic flip (1). Based solely on expectations—incumbent Republican in a lean-Republican state running for reelection in a strong Democratic year—Senator Joni Ernst of Iowa entered this election season no better than even money to win reelection. And now she trails businesswoman Theresa Greenfield by just under three points, with Greenfield’s margin increasing by 1.6 points after the conventions. This is enough to make Ernst a modest underdog—and this debate flub is likely to hurt Ernst even more.

Toss up (1). The Georgia special election is extremely difficult to assess, as I wrote earlier. Depending on which set of polls (all, or only post-conventions) we examine, the Democrat is either a one-point underdog or a three-point favorite—and that assumes a Democrat, as now seems very likely, makes the January run-off election. Given the extreme uncertainty surrounding this election, I consider it a toss-up.

Likely Republican flip (1). While Alabama Senator Doug Jones is outpacing his fundamentals—running as a Democratic incumbent after only three years in a very Republican state—by 9.6 points, he will almost certainly lose to former college football head coach Tommy Tuberville. In fact, losing “only” by mid-single-digits would be a moral victory for Jones.

Lean/likely Republican (4). There are four Republican-held Senate seats—in states averaging 16.8 points more Republican than the nation as a whole—which Democrats have between a 17% and 28% chance of winning, using all polls conducted since January 1, 2020; Democrats trail in these elections by an average 2.5 points. The outlook improves slightly when only post-convention polls are examined, with the average deficit dropping to 2.2 points.

Going from least to most likely to flip:

–In South Carolina, former state Democratic Party Chair Jaime Harrison has closed the gap with Senator Lindsey Graham from 4.0 points pre-conventions to 2.0 post-conventions, but still has only about a one-in-four chance of winning. Notably, a Harrison victory would give South Carolina two male African-American Senators, the other being Republican Tim Scott.

–In Montana, Democratic Governor Steve Bullock has lost ground recently to Senator Steve Daines, watching his deficit increase from 1.8 points to 2.7 points post-conventions, while his likelihood of prevailing has dropped from 26.3% to 17.5%.

–In the regularly-scheduled Georgia Senate election, journalist Jon Ossoff continues to narrow the gap with Senator David Perdue, who continues to perform in racist and anti-Semitic ways, climbing from 2.6 points to 1.5 points down after the conventions. I estimate Ossoff now has a roughly 30% chance of winning, up slightly from 25%.

–In the open seat in Kansas, which has not elected a Democrat to the Senate since 1932, State Senator (and former Republican) Barbara Bollier is mounting a surprisingly strong challenge to House Member Roger Marshall. Prior to the conventions, she had already narrowed the “expected” deficit from 16.2 points to 3.6 points. Since the conventions, she trails by only 0.7 points, giving her a 38% chance to win.

Assuming the outcomes in these four races are unrelated to each other—a poor assumption, to be sure—Democrats have a 70% chance of winning at least one of these races, with Georgia and Kansas being the most likely.

Likely Republican (3). Democrats—and one Independent—are at least making life uncomfortable for three Republican Senators seeking reelection: Dan Sullivan of Alaska, Cindy Hyde-Smith of Mississippi, and John Cornyn (Senate Majority Whip) of Texas. Orthopedic surgeon Gross has closed the gap against Sullivan from 6.0 to 3.7 points, though that still gives him only a 1-in-9 chance of winning. First-term Senator Hyde-Smith again faces former Agriculture Secretary Mike Espy, who lost by “only” 7.2 points in 2018. Through August, Espy trailed by double digits, but a poll by the partisan-netural Tyson Group in late August had him trailing just 40-41 (with an astonishing 19% undecided or choosing a different candidate), which narrowed the deficit to around 8.7 points overall. The previous Tyson Group poll, conducted in March, had Espy trailing by 26 points! Finally, United States Air Force veteran Mary Jennings “M. J.” Hegar continues to chip away at Cornyn’s lead, climbing from 7.8 points to 5.8 points down. All this being said, I still expect Sullivan, Hyde-Smith and Cornyn to win with low-to-mid-single-digit margins.

Safe Republicans (10). Senators Bill Cassidy of Louisiana, Ben Sasse of Nebraska, Mike Rounds of South Dakota, Tom Cotton of Arkansas, James Risch of Idaho, Shelley Moore Capito of West Virginia and James Inhofe of Oklahoma should easily win reelection by double-digit margins. And in Tennessee and Wyoming, respectively, former United States Ambassador to Japan Bill Hagerty and former House Member Cynthia Lummis are expected to win by similar margins. Finally, while former United States Marine fighter pilot Amy McGrath has run a spirited race in Kentucky against Republican Senate Majority Leader Mitch McConnell, she is still likely to lose by around 10 points.

In sum, Democrats appear all but certain to net at least one Senate seat, losing in Alabama while winning in Arizona and Colorado, and are very well-positioned to win seats in Maine, North Carolina and, with less certainty, Iowa, giving them a narrow 51-49 majority; Warnock defeating Collins or Loeffler in January would increase that lead to 52-48. The question then becomes whether Democrats can add further seats in Georgia, Kansas, Montana or South Carolina…and even pull off an upset or two in Alaska, Mississippi or Texas.

Here is another way to think about these races.

An old “rule of thumb” says an incumbent polling below 50% is likely to lose, because undecided voters—who presumably know a great deal about the incumbent—will break against her/him. In reality, undecided voters tend to break in unpredictable ways, albeit generally in the same partisan direction in so-called “wave” years. Given the tens of millions of votes which will already have been cast by November 3, which then get factored into polling, this year’s undecided voters are even harder to predict—and may even break strongly in favor of Republicans, simply by virtue of not having voted early.

Table 2 lists candidate post-convention polling averages, prior to adjustment for partisan pollster bias, in the 15 most competitive Senate races, sorted by Democratic percentage:

Table 2: Post-conventions polling averages for Democratic and Republican 2020 Senate candidates

North CarolinaYes46.8%41.4%
South CarolinaYes44.8%46.2%
Georgia–LoefflerYes41.9% total44.6% total
MississippiYes41.0% in 2 Aug polls44.0% in 2 Aug polls

Kelly and Hickenlooper in Arizona and Colorado, respectively, are already at or above 50%, as is Tuberville in Alabama, suggesting these races are all but over. Incumbents Collins and Tillis, in Maine and North Carolina, respectively, are struggling to crack 42%, while Ernst in Iowa and Loeffler/Collins are well below 45%. For that matter, Marshall is struggling to reach 44% in Kansas, which leans 23.4 points Republican! With just over two weeks left, it is hard to see these incumbents make up that ground with voters, even if none of their Democratic opponents are polling much higher than 47%. Mississippi, meanwhile, is very difficult to gauge: in five polls taken between January and May, Hyde-Smith leads by an unweighted 52-36, but in the two August polls that deficit drops sharply to 44-41. This truly is the sleeper race.

Four other Republican incumbents are hovering around 46%–Graham, Perdue, Sullivan and Cornyn—which is in a kind of gray area between safe and in serious trouble. The good news for the latter two is that their opponents are struggling to top 42%. The bad news for Graham and Perdue is that their opponents are hovering around 45%–making undecided voters truly decisive in these two elections.

Peters in Michigan and Smith in Minnesota are hovering just below 48%, meanwhile, though they are still well ahead of their Republican opponents, who average around 40%. Daines in Montana, finally, is at 48.5%, close enough to 50% that Bullock may have a hard time catching him.

Bottom line: Democrats currently appear poised to pick up at least four seats, giving them a 51-49 majority. They are at least even money to win the Georgia special election and have at least modest opportunities to flip one or more of seven other Republican-held seats. If I simply sum the probabilities Democrats win each race, I get +5.1 using all polls and +6.0 using only post-conventions polls, though this is very “back of the envelope” methodology. Still, while Democrats could still net only one or two seats, a net gain of three-six seats is by far the likeliest outcome.

The strong likelihood of Democrats regaining control of the Senate is boosted by two historically-plausible scenarios:

  1. All polls are overestimating Democratic margins by 3.0 points.

In this scenario, Democrats remain strongly favored in Arizona (90.8%) and Colorado (97.3%) while headed for certain defeat in Alabama (0.0%), and they would be favored in Maine (74.0%) and North Carolina (75.5%), with Iowa essentially a toss-up (44.2%). Michigan would begin to get dicey as well, though Peters would still be an 89.0% favorite. Democrats would not be favored by more than 10% (Georgia special election) in any other race, though they would probably just net the three seats they need to regain control. The “back of the envelope” estimate is Democrats winning 2.9 seats, making control toss-up/Lean Democrat.

  • All polls are underestimating Democratic margins by 3.0 points.

While Alabama is still a near-lock to flip Republican, Democrats would be at least a 95.6% favorite to win Arizona, Colorado, Iowa, Maine and North Carolina for a minimum net gain of four seats. Democrats would also be 3-1 favorites in the Georgia special election, and the Senate races in South Carolina (51.0%), Georgia (61.9%), Montana (63.0%) and Kansas (64.7%) would be toss-ups, with Democrats likely to win at least two of them. They would also have a 35.2% chance of winning Alaska, and even a 13.6% chance of winning Texas. The “back of the envelope” estimate is Democrats netting 7.6 seats, making control a near-certainty, with a net 9-11 seats plausible, if still unlikely.


Very little has changed in the 11 states holding gubernatorial elections in 2020. Regardless of which polls you examine or what over- or under-estimation assumptions you make, Republicans are heavily favored to hold governor’s mansions in Vermont, New Hampshire, Indiana, Missouri, West Virginia, North Dakota and Utah. The closest margin is Missouri, where State Auditor Nicole Galloway trails Governor Mike Parson by an estimated 8.3 points. Similarly, Democrats are heavily favored to retain governor’s mansions in Delaware, Washington and North Carolina by double-digit margins, while Republican House Member Greg Gianforte is very likely to win back the Montana governor’s mansion—he leads Democratic Lieutenant Governor Mike Cooney by an estimated 7.4 points—for the first time in 16 years. Thus, Republicans will almost certainly net one governor’s mansion this year, increasing their edge to 27-23.

Until next time…please stay safe and healthy…

[1] That is, some variant of “If the election for United States House of Representatives was held today, would you vote for the Democrat or the Republican in your Congressional district?”

[2] Rhode Island, Illinois, Tennessee, Nebraska, South Dakota, Wyoming

Biden is now the clear favorite to win the 2020 presidential election

On November 3, 2020, a weeks-long presidential election between incumbent Republican Donald J. Trump and his Democratic challenger, former Vice President Joseph R. Biden, Jr., will end. As I write this, more than 23 million Americans—including yours truly—have already cast their ballots. This number is just over 1/6 of total votes cast in 2016.

Following an extremely contentious first presidential debate on September 29, and dueling town hall events on October 15, here is an updated assessment of the 2020 presidential election; you may find my previous assessment here. Assessments are based upon all publicly-available polls of the presidential election—nationally and by state, recognizing presidential elections are determined by the Electoral College—conducted since January 1, 2019.

A total of 606 national polls assessing Biden vs. Trump have been conducted since January 1, 2019,[1] of which:

  • 499 have been conducted since January 1, 2020
  • 140 have been conducted entirely since the end of the national party conventions on August 28
  • 44 have been conducted entirely since the first presidential debate

The 70+ pollsters who have assessed this election at least once have an average B- FiveThirtyEight pollster rating, as do the 50+ pollsters who have assessed the election multiple times.

Figure 1 shows how Biden has fared monthly against Trump in 2020, using my weighted-adjusted polling averages (WAPA). I use pollster rating data to adjust for partisan lean (historic tendency to err more Democratic or Republican than other pollsters in analogous races) and quality.[2] I weight more recent polls higher, using the number of days since January 1, 2019 divided by 673, the number of days between January 1, 2019 and November 3, 2020. I then average two versions of WAPA: one treating polls by the same pollster as statistically independent, and one treating all polls by the same pollster as a single, time-weighted value; differences between estimates are usually negligible. Polls conducted after August 28, but before September 30, are weighted 1.5 times higher than prior polls, and polls conducted entirely after September 29 are weighted 3.0 times higher.

Figure 1

Using all polls conducted since January 1, 2019, Biden leads Trump nationally by 8.2 percentage points (“points”), with his lead rising to 8.8 points only using polls conducted since the conventions, and to 9.9 points only using the 46 polls with an October 2020 field date midpoint. Biden’s margin over Trump has risen from just over four percentage points in January and February, when he was fighting for the 2020 Democratic presidential nomination, to just under six points in the three months after Biden’s decisive win in the 2020 South Carolina Democratic presidential primary, to between seven and 10 points since June 1, the day protesters were forcibly cleared from Lafayette Square so Trump could pose in front of St. John’s Episcopal Church holding a copy of the Bible.


Again, though, presidential elections are fought across 50 states and the District of Columbia (“DC”), with the plurality winner in each state/DC winning every electoral vote (“EV”) from that state. Now that SurveyMonkey—a D- pollster with a 5.0-point historic Democratic bias—has released a set of polls covering June, July, August and September, every state/DC has now been polled at least four times.

Table 1 reports two projected Democratic-minus-Republican margins and corresponding EV win percentage (“EV%”) for every state and DC: one using all polls conducted since January 1, 2019, and one using only polls conducted since the two national party conventions. The table is sorted from highest to lowest EV% using the larger set of polls. For margin and EV% calculations, see here.

Table 1: Projected 2020 Biden-Trump margins and likelihood of winning EV calculated two ways

StateMargin since 1/1/2019EV%Margin since 8/29/2020EV%
New York27.1100.0%31.4100.0%
Rhode Island16.8100.0%23.4100.0%
New Jersey19.3100.0%19.5100.0%
New Mexico11.899.9%12.999.9%
New Hampshire7.899.0%8.999.4%
North Carolina1.871.7%1.973.4%
South Carolina-7.70.9%-7.61.0%
South Dakota-22.10.0%-19.50.0%
North Dakota-23.30.0%-21.30.0%
West Virginia-21.50.0%-16.70.0%

With just 17 days until Election Day 2020, Joe Biden is the clear favorite to be elected the 46th president of the United States. The most direct way for Biden to win the Electoral College is to win the 232 EV from the states won by Democratic presidential nominee Hillary Clinton won in 2016, then add Michigan (98.9%), Wisconsin (96.8-98.2%) and Pennsylvania (96.1-96.7%); he could even lose Nevada (92.0-96.2%) and still win 273 EV, three more than necessary. Taking the product of the likelihood of victory for the states totaling 273 EV yields a minimum 89.5% probability Biden wins the Electoral College using all polls, which rises to 91.8% using only post-convention polls. These are very rough probabilities given how correlated voting behavior is across demographically-similar states, though they are broadly in line with other public estimates.


  • He is at least a 92.0% favorite in enough states—and by margins of at least 4.5 points—to earn him 278 or 279 EV, depending on what happens in Maine, which, along with Nebraska, allocates two EV to the statewide winner and one each to the winner of its Congressional districts. At this point, Biden would already have won the presidency.
  • He is favored better than 4-1 to win the 11 EV of Arizona and the 29 EV of Florida, by around three points each, increasing Biden’s total to 318 or 319 EV.
  • He is favored 5-2 to win North Carolina, by a hair under two points, for an additional 15 EV, increasing Biden’s total to 333 or 334 EV.
  • The 40 combined EV of Ohio, Georgia and Iowa are essentially toss-ups, with projected margins of less than one point, increasing Biden’s total to between 339 and 375 EV; Biden has a roughly 81% chance of winning at least one of them. That said, winning Iowa would require a winning a solid majority of undecided voters, Ohio has been trending slightly away from Biden, and Georgia is literally 50-50.

Plus, it might take only a sharp break by undecided voters and a modest polling error for Biden to win the ultimate prize—Texas (-2.1). Thus, while something in the mid-300’s currently appears the most likely EV total for Biden, 413 (or more) EV cannot be discounted.

Using the simplistic—perhaps even simple-minded—method of multiplying Biden’s probability of winning each state by its EV, then summing, yields a “projected” EV total of just under 350 EV using both sets of polls, essentially adding Michigan, Pennsylvania, Wisconsin, Florida, Arizona, North Carolina, and one of Ohio/Georgia/Iowa to the states Clinton won.

Biden’s lead looks even stronger after making either of two historically-valid assumptions; calculation use all polls conducted since January 1, 2019:

Polls systematically overestimate Biden’s margins by 3.0 points.

In this scenario, Biden’s projected EV drops to 300.8, 28.8 more than required, with a minimum “path of least resistance” probability of 51.0%. He would be favored at least 78.8% to win in enough states to win 273 EV. Thus, even if Biden “only” wins the national popular vote by 5.2 points, he would likely still prevail, though the decisive states of Wisconsin and Pennsylvania would be decided by relatively narrow margins, with all votes possibly not counted for a week or more. That Biden could win the national popular vote by more than five points, yet still only be a modest favorite to win at least 270 EV, demonstrates the recent Republican advantage in the Electoral College.

Polls systematically underestimate Biden’s margins by 3.0 points.

In this scenario, Biden’s projected EV are a landslide-level 390.3, 120.3 more than necessary, with a minimum “path of least resistance” probability of 97.2%.  He would be favored at least 80% to win enough states to earn 368 EV, while being a 3-1 favorite in Iowa, for a total of 374 EV. Biden would even be a slight favorite (61.7%) in Texas, which he would be projected to win by 0.8 points. Biden would also have a 20.4% chance of winning Alaska’s 3 EV and a 10.4% chance of winning Missouri’s 10 EV. The last presidential candidate to come close to 426 EV was Republican George H. W. Bush, who won 426 EV in 1988.


None of this is to say Biden is guaranteed to be elected the next president of the United States. Even with the massive surge in early voting, delays in mail delivery—allegedly orchestrated by the Postmaster General—could leave millions of votes uncounted because they did not arrive by November 3. Pennsylvania, the most likely “tipping point” state—the one giving either Biden or Trump the necessary 270 EV when states are ordered most to least Democratic—is already showing the strain of trying to establish absentee voting on the fly. Moreover, while Biden’s national polling lead has ranged between seven and 10 points since June 1, a last-minute “October surprise” could erase this lead, though this “e-mails” story is unlikely to be it.

Nonetheless, unlike Clinton in 2016, Biden has a sufficiently-wide range of paths to 270 EV that I estimate he is at least a 92% favorite to be elected president of the United States on November 3, 2020—or whenever ballots are ultimately counted.

Until next time…please stay safe and healthy…

[1] I limit iterations of tracking polls only to those with non-overlapping field dates.

[2] I halve the number value assigned to a letter grade for any poll conducted since June 1, 2020 which samples adults instead of registered or likely voters.