One defining feature of the Democratic primary so far has been the party’s leftward turn. In recent debates, candidates have supported policies like offering health insurance to undocumented immigrants, and commenters have warned about the potential electoral penalty of repelling persuadable voters.
Political science research suggests that moderates generally fare better in elections, but much of our current understanding is speculative: There has been little directly relevant data on how voters are reacting in the moment. Are swing voters being put off? Are Democratic voters excited and more likely to stick with their party?
In a recent survey experiment I conducted, the evidence pointed to both these possibilities, but with one pattern much more pronounced than the other.
The embrace of progressivism solidifies support among Democratic survey respondents when thinking about the 2020 general election. But it repels independents, with a negative effect that is stronger and clearer than the signs of enthusiasm generated among Democrats.
It may be early, but the proposals from primary candidates can already have an effect, as the survey experiment showed. (It was administered to 3,973 Americans on the online panel of the Democratic data firm Civis Analytics over the course of a week in mid-August, after the first two Democratic debates.)
The experiment’s procedure was simple. A random half of participants read a news snippet illustrating the leftward shift, while the other half read about unrelated topics, such as the schedule of election dates. The news item was a few sentences that included policies discussed by the candidates: decriminalizing unauthorized border crossings; expanding undocumented immigrants’ access to government services; replacing private health insurance with a government-run system; and establishing free public college for all children from working-class families. The content was drawn directly from real news coverage.
Both sets of respondents then indicated how they planned to vote in 2020 (whether for President Trump or the eventual Democratic nominee), how strongly they were considering voting Democratic, and how motivated they felt to turn out and vote for or against the Democratic nominee. Because of the random assignment — with some reading about the policy positions and others reading innocuous, unrelated information — the difference in responses between the groups can be attributed to the effect of reading about the leftward shift.
When deciding between Mr. Trump and the Democratic nominee, voters in the middle — the independents who could ultimately tilt things in Mr. Trump’s favor — became six percentage points less likely to vote Democratic after reading about the leftward turn compared with the independents who had read the innocuous content.
Democrats and Republicans were much more settled in their vote preferences than the independents in the survey. But when Democrats who’d read the news snippet were asked how strongly they would consider voting for their eventual nominee, they moved more emphatically in support (by three points on a “strength of consideration” scale). This suggests the possibility of limiting future defections among Democrats.
At the same time, playing to the Democratic base seems to have its limits, with no evidence suggestive of mobilization potential. Democrats who read about the leftward positions did not indicate they were more motivated to vote and campaign for the eventual nominee than those who hadn’t read about them.
The results suggest a double-edged sword, but with one clearly sharper side: the potential of producing Republican gains among a key swing group.
Of course, the election is far away. Some progressive policies are broadly popular, and Democrats may choose to focus on them. In the transition from the primary to the general election, a candidate might moderate in tone, and the proposals voiced in current debates could fade from memory by next year.
It’s also possible that Democrats would lose a certain segment of independents no matter the positions they adopted — during the phase of the campaign when Republicans deploy attack ads. As Pete Buttigieg put it, Republicans are “going to say we’re a bunch of crazy socialists” anyway, so “let’s stand up for the right policy, go up there and defend it.”
That may well be the right approach, but the question is, are Democrats giving Republicans a head start and making themselves a juicier target? This experiment suggests the answer might be yes.
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