All it takes to reduce support for housing assistance among Donald Trump supporters is exposure to an image of a black man.

That’s the takeaway from a new study by researchers Matthew Luttig, Christopher Federico, and Howard Lavine, set to be published in Research & Politics. In a randomized survey experiment, the trio of researchers exposed respondents to images of either a white or black man. They found that when exposed to the image of a black man, white Trump supporters were less likely to back a federal mortgage aid program. Favorability toward Trump was a key measure for how strong this effect was.

The study is just the latest to show that racial attitudes are a powerful predictor for support for Trump — and the newest to suggest that such attitudes play a major role in Americans’ views toward public policy. Previous studies have found that racial resentment was a much stronger indicator of support for Trump than views about the economy. And other research has shown that priming people to think about race can make them more conservative on a host of issues.

This latest study is notable, though, because all it uses is an image of a black man to produce its results. That suggests that Trump has a powerful incentive to get people to keep thinking about race: If his most ardent supporters just need a slight racial cue to come around to his conservative policy views, then Trump simply has to bring up race to get his supporters fired up for him.

What the study found

For the study, researchers deployed a survey experiment, sampling more than 700 white people on their support housing assistance programs. (The researchers only used data from white respondents because support among minority groups for Trump was too low to be statistically reliable.) But there was a twist: Respondents were randomly assigned “a subtle image of either a black or a white man.”

They found that the image of a black man greatly impacted responses among Trump supporters. After they were exposed to the black racial cue, they were not only less supportive of housing assistance programs, but they also expressed higher levels of anger that some people receive government assistance and were more likely to say that individuals who receive assistance are to blame for their situation.

All of these findings were heightened with greater favorability for Trump. In fact, there was an opposite effect among respondents who reported the least favorability toward Trump: They were less likely to oppose housing assistance, get angry at the program, or blame the recipients of such programs for their situation when exposed to the black racial cue compared to the white racial cue. (Luttig told me that this is likely a result of racial progressives viewing black people as disadvantaged in America due to structural racism, therefore requiring more aid.)

In contrast, favorability toward Clinton did not significantly change respondents’ views on any of these issues when primed with racial cues.

The researchers concluded, “These findings indicate that responses to the racial cue varied as a function of feelings about Donald Trump — but not feelings about Hillary Clinton — during the 2016 presidential election.”

The researchers, which generally controlled for a host of socioeconomic and demographic variables, also tested to see whether measures of polarization or ideology changed the findings. They found little to no effect.

“Support for Donald Trump — not partisanship or ideology — uniquely captures distinct reactions to our experimental manipulation of race,” they conclude. “That is, support for Donald Trump appears to serve as a basis for polarized responses to racial cues in its own regard.”

One caveat to the study: It’s not clear if the results are reflective of higher support due to a white racial cue or lower support due to the black racial cue. It’s possible that it’s not that Trump supporters are made less likely to support housing assistance when exposed to the image of a black man, but that they are made more likely to support housing assistance when exposed to the image of a white man. The researchers said that they will need further study to clarify this, along with questions of how racial cues affect views on other policy issues among Trump supporters.

Still, the study is not the first of its kind to produce these kinds of findings. Time and time again, researchers have found that racial attitudes play a major role in support for Trump and US politics more broadly.

A lot of studies show racial attitudes are a big deal in US politics

The most straightforward research in this area looks at how views on race influenced support for Trump.

One paper, published in January by political scientists Brian Schaffner, Matthew MacWilliams, and Tatishe Nteta, found that voters’ measures of sexism and racism correlated much more closely with support for Trump than economic dissatisfaction after controlling for factors like partisanship and political ideology.

And one telling study, conducted by researchers Brenda Major, Alison Blodorn, and Gregory Major Blascovich shortly before the election, found that if people who strongly identified as white were told that nonwhite groups will outnumber white people in 2042, they became more likely to support Trump. That suggested that there’s a big racial element to support for Trump.

Along similar lines, there’s research, previously covered by Dylan Matthews for Vox, that looks at how priming people to think of race can change their policy views.

In one study, Harvard political scientist Ryan Enos had Spanish-speaking Latino men ride commuter trains in Boston. He surveyed other riders before and after they were exposed to the Latino men to see how it changed their views on immigration, while using surveys of those who were never exposed to the Latino men as a control.

“The results were clear,” Enos wrote in the Washington Post. “After coming into contact, for just minutes each day, with two more Latinos than they would otherwise see or interact with, the riders, who were mostly white and liberal, were sharply more opposed to allowing more immigrants into the country and favored returning the children of illegal immigrants to their parents’ home country. It was a stark shift from their pre-experiment interviews, during which they expressed more neutral attitudes.”

There’s yet another line of research that’s suggestive on this.

As researchers Sean McElwee and Jason McDaniel explained for Vox, racial attitudes are a very strong predictor for beliefs about government spending. “For decades, social scientists have found that attitudes about race, particularly toward African Americans, persistently impact political attitudes and opinions toward government services, spending, and welfare,” they wrote.

McElwee and McDaniel measured racial resentment, economic peril, and support for more government spending. They found that higher measured racial resentment correlated with a preference for decreased government spending and services, while more economic insecurity appeared to correlate — but not at a statistically significant level — with more support for increased government spending.

Similarly, other studies have linked greater racial resentment to more support for “tough on crime” policies.

In short, racial attitudes are a powerful predictor for a host of political issues, and racial priming can push people in a more conservative direction. That just so happens to be beneficial for Trump, whose policy agenda is built largely on cracking down on immigration, bringing back “tough on crime” policies, and cutting taxes for the rich and services to the poor.

So with all his racist comments on the campaign trail, Trump not only pandered to his biggest fans, but likely got more people to think in a direction that favored his agenda.