Supporters of Democratic presidential candidate Bernie Sanders attend an election night rally in Carson, Calif., on  May 17, 2016. (ROBYN BECK/AFP/Getty Images)

Are Bernie Sanders supporters more ideologically liberal than Hillary Clinton supporters? The conventional wisdom — that of course they are — was challenged last week when political scientists Christopher H. Achen and Larry M. Bartels wrote about some surprising findings in the New York Times.

Achen and Bartels analyzed 2016 American National Election Study (ANES) pilot survey data to figure out Sanders supporters’ attitudes on social welfare issues like the minimum wage and health care spending. According to their data, respondents who prefer Sanders held roughly the same positions as – or were more conservative than – Clinton voters, overall.

How can that be? According to DW-NOMINATE scores, Sen. Sanders had a more liberal Congressional roll call voting record than Clinton did as a senator. Sanders’s campaign has been dedicated to a very liberal – even moderately socialist – redistribution of wealth: a higher minimum wage, a “Medicare for all” federal healthcare plan and economic inequality reduced by redistributing income from the rich to everyone else.

If his supporters don’t actually favor those plans, we would have to question whether American voters know how to pick candidates whose ideologies and policies match their own.

Achen and Bartels failed to account for this part of the data

But here’s one part of the 2016 ANES pilot study that may undermine Achen and Bartels’s conclusions. The study asked Democrats, independents, and Republican respondents alike to say which Democratic primary candidate they preferred: Hillary Clinton, Martin O’Malley, Bernie Sanders, “another Democratic candidate,” or none.

More than twice as many Republican respondents chose Sanders as chose Clinton.

That means that in analyzing this group of Sanders “supporters,” Achen and Bartels were examining a group that may well have been farther to the right than actual Sanders voters. We don’t believe that the ANES Republican respondents were actually Sanders backers. We think it’s far more likely that they just strongly dislike Hillary Clinton.

Here’s how we tested our hypothesis

We tested this hypothesis using the study’s “feeling thermometers,” which ask respondents to rate how warmly they feel about a series of political figures using a 100-point scale. A rating of 0 is a very cold or unfavorable feeling; a 100 rating is a very warm or favorable feeling.

Republicans who said that they preferred Sanders over all the other Democratic candidates didn’t actually like him. They gave him very lukewarm ratings, an average of 53 degrees. But they really, really disliked Hillary Clinton, rating her at a very cold 15 degrees. By contrast, Democrats and independents who preferred Sanders over the other Democratic candidates rated him, on average, at 84 degrees.

In other words, to find out what policies Sanders voters support, we’ll do better if we leave out Republicans’ beliefs entirely. Analyzing only the beliefs of the Democrats and independents who support Sanders will give us a more accurate picture.

If you take out the Republicans, here’s what actual Sanders supporters say

We looked at respondents who identified as strong or weak Democrats, Democratic-leaning independents, and pure independents. Among this group, Sanders supporters are in fact more liberal than Clinton supporters across a host of issues. The differences aren’t substantial, but they are consistent. For instance, 87 percent of Sanders supporters are favor raising the minimum wage, while 79 percent of Clinton supporters do.

As you can see in the figure below, Clinton and Sanders supporters differed most on which issues they consider most important. For example, about half of Sanders supporters rank income inequality as one of their top four most important issues, 39 percent place the environment and climate change up top as well. Clinton supporters are somewhat more likely to rank issues like economic growth, education, gun control and terrorism/homeland security among their top issue priorities.

But on some issues, Clinton and Sanders supporters differ very little, if at all. For instance, nearly half of both groups say that police treat whites much better than blacks.


In other words, on most issues, actual Sanders supporters – Democrats and independents who voted for him or would be likely to, as opposed to Republicans who are holding their noses and selecting the Democrat they dislike least – are indeed to the left of Clinton supporters. Primary voters are in fact able to pick the candidate whose positions they find most ideologically compatible. And that lines up more accurately with other scholarly evidence (see, for example, here and here).

Christopher Hare is an assistant professor at the University of California, Davis.

Robert Lupton is visiting assistant professor at Michigan State University and managing editor of the American Journal of Political Science.