In Defying the Odds, we talk about the social and economic divides that enabled Trump to enter the White House. In Divided We Stand, we discuss how these divides played out in 2020. In both elections, however, polls tended to overstate Democratic margins.
Many pollsters now worry whether survey respondents are too Democratic-leaning relative to the electorate. In this survey, 40% of the respondents identify as Democrats and 31% identify as Republicans, even after weighting the data to match the demographics of the 2020 electorate.
But it’s not clear whether this Democratic-leaning sample is a problem. It does not match some other polls, which suggest a narrower party divide. But if Democrats end up being more mobilized to vote in 2024, this partisan imbalance could be a feature of this year’s electorate.
Or maybe not. It could be that Democratic voters are just more likely to take this poll – as was the case in 2020.
If it’s the latter, then the sample is “too Democratic” and needs to be adjusted further. Two common approaches are to weight the sample by partisanship or by self-reported vote in the last presidential election. But again, the right benchmark isn’t obvious.
For partisanship, pollsters often rely on benchmarks such as the Pew Research Center’s National Public Opinion Research Sample, which suggests that the country is evenly split – 33% Democrat, 32% Republican, and 35% independent – or Gallup’s tracking survey, which suggests that 28% are Democrats, 31% are Republicans and 41% are independents. If I adjust the raw data by both the demographics of the 2020 electorate and these party identification benchmarks, Harris’ margin is greatly reduced relative to the raw data and demographics alone:
Raw data: +6.0 Harris
2020 demographics: +9.0
2020 demographics + Pew party identification: +3.9
2020 demographics + Gallup party identification:+0.9
