August 2019 update: 2020 Democratic presidential nomination and general election polling

It has been just over two weeks since the second Democratic presidential nomination debates, so it is time for an updated assessment of the relative position of the 23 declared candidates remaining. Former Alaska Senator Mike Gravel ended his campaign on August 6, 2019, and it appears former Colorado John Hickenlooper will end his bid on August 15, 2019.

To learn how I calculate NSW-WAPA (national-and-state-weighted weighted-adjusted polling average), please see here[1]. Note that I recently altered my methodology slightly: within my post-early-state weighted average of each candidate’s WAPA, I now weight the nine states[2] scheduled to hold their nomination contests on March 3, 2019 (“Super Tuesday”) twice as much as all subsequent contests[3]

And, as usual, here is the August 2019 lighthouse photograph in my Down East 2019 Maine Lighthouses wall calendar.

Aug 2019 lighthouse.JPG

Table 1 below aggregates data from all national and state-level polls publicly released since January 1, 2019, including:

  • 149 national polls (including 32 weekly Morning Consult tracking polls)
  • 19 Iowa Caucuses polls
  • 22 New Hampshire Primary polls
  • 4 Nevada Caucuses polls
  • 18 South Carolina polls
  • 35 Super Tuesday polls[4]
  • 33 polls from 13 other states.[5]

This makes a total of 280 polls, up from 247 in the last update.

Table 1: National-and-state-weighted WAPA for declared 2020 Democratic presidential nomination candidates

Candidate National IA NH NV SC Post-SC NSW-WAPA
Biden 29.5 23.6 23.3 30.2 36.4 27.3 27.9 (-0.7)
Sanders 16.7 15.1 19.0 19.1 12.6 15.3 16.4 (-0.1)
Warren 10.4 13.1 13.5 18.0 9.1 12.6 13.2 (+0.6)
Harris 8.6 9.7 8.7 8.6 9.9 9.7 9.2 (–)
Buttigieg 5.6 9.1 9.1 8.0 4.9 6.7 7.7 (-0.3)
O’Rourke 4.1 2.6 2.2 3.1 1.8 5.3 2.8 (-0.3)
Booker 2.5 2.5 1.6 1.3 3.5 1.5 2.2 (-0.2)
Klobuchar 1.3 2.7 1.5 1.1 0.6 1.0 1.5 (–)
Yang 1.0 0.7 1.3 1.5 0.7 0.7 1.1 (–)
Gabbard 0.7 0.6 1.4 1.1 0.3 0.5 0.84 (+0.11)
Castro 0.9 0.7 0.2 1.0 0.1 1.0 0.59 (–)
Gillibrand 0.5 0.6 0.7 0.4 0.3 0.3 0.50 (+0.09)
Delaney 0.3 0.9 0.5 0.00 0.3 0.2 0.43 (–)
Steyer 0.03 0.1 0.4 1.0 0.4 0.1 0.40 (+0.30)
Inslee 0.4 0.4 0.2 0.3 0.1 0.3 0.26 (+0.06)
Williamson 0.2 0.05 0.3 0.4 0.3 0.1 0.24 (+0.07)
Bennet 0.2 0.3 0.2 0.00 0.2 0.4 0.20 (+0.04)
Ryan 0.3 0.1 0.3 0.00 0.2 0.2 0.16 (-0.01)
Bullock 0.2 0.3 0.00 0.00 0.1 0.1 0.10 (+0.03)
de Blasio 0.3 0.05 0.00 0.00 0.1 0.1 0.04
Moulton 0.1 0.04 0.1 0.00 0.00 0.03 0.03
Messam 0.00 0.00 0.00 0.00 0.1 0.04 0.03
Sestak 0.00 0.1 0.00 n/a 0.00 0.06 0.02
DK/Other 14.6 15.8 15.0 4.4 16.9 16.0 13.7 (+0.4)

There has been little substantive change in the relative standing of the 23 remaining candidates over the last two-three weeks, despite some short-term effects from the second round of debates (see below). Former Vice President Joe Biden remains the nominal frontrunner (27.9), primarily because of his dominant position in South Carolina primary polls; his weighted average of 36.4% is well ahead of Vermont Senator Bernie Sanders, California Senator Kamala Harris and Massachusetts Senator Elizabeth Warren. By contrast, the race is much closer in polling for the Iowa Caucuses and New Hampshire Primary; in these first two contests, Biden is only averaging 23-24%, with Sanders close behind at 15-19% and Warren at 13-14%. Harris and South Bend, Indiana Mayor Pete Buttigieg are not much further behind, hovering around 9%.

These five candidates continue to dominate the race overall, albeit with Biden continuing to decline while Warren continues her steady ascent (up from 8.5% in early June to 13.2% now), capturing just under three-quarters of the support of those polled. Just behind these five are four other candidates with an NSW-WAPA of 1.0 or higher: former Texas member of the United States House of Representatives (“Representative”) Beto O’Rourke, New Jersey Senator Cory Booker, Minnesota Senator Amy Klobuchar and entrepreneur Andrew Yang. Perhaps not surprisingly, these are also the only nine candidates to have qualified for the next round of Democratic presidential nomination debates (September 12-13, 2019). Overall these nine candidates account for 81.9% of currently-declared Democratic nomination preferences. Factor in 13.7%s[6] undecided or choosing an unlisted candidate, that means the remaining 14 candidates are divvying up just 4.4% between them.


In the previous update, I assessed the short-term impact of the first round of Democratic presidential nomination debates by comparing support for each candidate in polls conducted by the same pollster within one month prior to, and just after, those debates. Meeting these criteria for the second round of debates are six national polls[7] and one Texas poll[8]. For ease of presentation, Table 2 presents data only for the 12 candidates with an NSW-WAPA of 0.5 or higher (including Hawaii Representative Tulsi Gabbard, former Secretary of Housing and Urban Development Julián Castro and New York Senator Kirsten Gillibrand). Values listed are simple arithmetic averages (with the Texas poll change weighted twice the changes in national polls); weighting by pollster quality or time between polls made little difference.

Table 2: Average change in polls from the same pollster before and after July 2019 Democratic presidential debates:

Candidate National TX Weighted Average
Biden -1.0 +4.5 +0.4
Sanders +1.8 +4.0 +2.4
Warren +1.8 +1.0 +1.6
Harris -3.5 -3.0 -3.4
Buttigieg +0.3 +3.0 +1.0
O’Rourke -0.3 -14.5 -3.9
Booker +0.8 +1.0 +0.9
Klobuchar -0.5 0 -0.4
Yang -0.3 +2.0 +0.3
Gabbard +0.3 0 +0.3
Castro -0.2 +2.0 +0.4
Gillibrand -0.2 0 -0.1
DK/Other +1.0 -1.0 +0.5

Examined this way, support for Harris—who had risen 7.7 percentage points (“points”) following the June debates—dropped fully 3.4 points following the July 2019 Democratic debates. O’Rourke also declined significantly (-3.9 points), but that was almost exclusively due to an astonishing 14.5-point drop (from 38% to 23.5%) in the Texas poll. The largest post-July-debate increases were for Booker (+0.9), Buttigieg (+1.0), Warren (+1.6) and Sanders (+2.4); no other candidate saw her/his support shift by more than 0.4 points in either direction. Finally, the percentage not choosing a listed candidate increased slightly.


To the extent that the polling for the 2020 presidential election between a named Democrat and Republican Donald J. Trump changed, it is due to the modestly-increased likelihood (55.7%) that someone other than Biden (who would hypothetically beat Trump nationally by 8.4 points) and Sanders (by 5.2 points) will be the 2020 Democratic presidential nominee. Thus, once you weight for the likelihood of being the nominee, the Democrat would beat Trump by 3.6 points. This is actually slightly higher than the median Democratic presidential margin (+3.0 points) in the previous six presidential elections, which include three elections with an incumbent seeking reelection and three elections with no incumbent. However, once you exclude Biden and Sanders, the margin over Trump decreases to 0.7 points; Warren would hypothetically win by 1.5 points and Harris by 1.0 points, while Buttigieg would lose by 1.5 points.

Still, given that state-level results actually determine the winner of a presidential election (via the Electoral College), it is more informative to look to those polls, where they are publicly-available. Using my 3W-RDM, a measure of how much more or less Democratic a state’s voting is relative to the nation as a whole, this polling[9] implies Democrats would win the national popular vote by between 2.6 (excluding former Vice President Joe Biden and Vermont Senator Bernie Sanders) and 5.6 (including Biden and Sanders) points on average. Most encouraging to Democrats should be the polls from North Carolina (R+6.0) and Texas (R+15.3), which show a very close race, implying a 6-7-point win and a 12-14-point win nationally for Democrats, respectively; these polls confirm strong opportunities for Democrats in the southeast and southwest. By contrast, however, a few polls from Democratic-leaning Maine (D+5.9) and Nevada (D+2.0) imply Democrats would lose nationwide by 2-5 points. Those remain the exceptions, however, to what continues to be encouraging news for Democrats in 2020.

Until next time…

[1] Essentially, polls are weighted within areal units (nation, state) by days to the nominating contest and pollster quality to form a unit-specific average, then a weighted average is taken across Iowa (weight=5), New Hampshire (5), Nevada (4), South Carolina (4), the time-weighted average of all subsequent contests (2) and nationwide (1).

[2] Alabama, California, Colorado, Massachusetts, Minnesota, North Carolina, Oklahoma, Tennessee, Texas, Virginia

[3] As of this writing, I have at least one poll from (in chronological order) Maine, Michigan, Mississippi, Missouri, Ohio, Washington, Arizona, Florida, Georgia, Wisconsin, Pennsylvania, Indiana and Oregon

[4] Primarily from California (14) and Texas (9)

[5] Primarily Florida (9) and Pennsylvania (5)

[6] This does include polls that limit the number of candidates queried.

[7] Morning Consult Tracking, HarrisX, Change Research, Quinnipiac University, YouGov, Reuters/Ipsos

[8] University of Texas at Tyler

[9] From Pennsylvania, New Hampshire, Wisconsin, Michigan, North Carolina, Texas, Iowa, Arizona, South Carolina, Minnesota, Nevada, Massachusetts, Florida, New York, Kentucky, Maine, Ohio.

Published by Matt Berger

I am a data geek, writer, investigator and film noir devotee with academic training in political science (Yale BA, Harvard MA), biostatistics (Boston University SPH MA) and epidemiology (Boston University SPH PhD). In January 2021, I finished writing Interrogating Memory: Film Noir Spurs a Deep Dive Into My Family History...and My Own for which I seek a publisher. In Chapter 6: So...What Is Film Noir, Again?, I analyze my film noir database, which contains 4,825 titles. My musical holy trinity is Genesis, Miles Davis and Stan Ridgway. I am a liberal Democrat who understands a thriving democracy requires at least two mature political parties. I grew up just outside Philadelphia, and I live just outside Boston, where my wife and daughters keep me happy, sane and grounded. Please ask me anything else you want to know.

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