In a Republican debate last month, Donald Trump was asked whether his claim that “Islam hates us” means all 1.6 billion Muslims worldwide hate the United States.

“I mean a lot of ’em,” Trump replied, as some in the crowd — Trump supporters, presumably — laughed and applauded.

That ugly moment comes to mind in describing how many of Trump’s supporters have racist motivations for backing him: Not all — but a lot of ’em.

Just as it’s unfair to paint all Trump backers as bigoted, it’s impossible to ignore a growing volume of public-opinion data showing that a large number of his supporters are indeed driven by racial animus.

A Pew Research Center national poll released Thursday found that 59 percent of registered voters nationwide think that an increasing number of people from different races, ethnic groups and nationalities makes the United States a better place to live; only 8 percent say this makes America worse. But among Trump backers, 39 percent say diversity improves America, while 42 percent say it makes no difference and 17 percent say it actually makes America worse. Supporters of GOP rivals Ted Cruz and John Kasich were significantly more upbeat on diversity.

At a rally in Allendale, Mich., Friday, Democratic presidential candidate Bernie Sanders slammed Republican presidential frontrunner Donald Trump, saying Trump will be defeated because the American people don't want a president who insults Mexicans, Muslims, or women. (Reuters)

This was no anomaly. The week before, my Post colleagues Max Ehrenfreund and Scott Clement reported on a Post/ABC News poll that asked whether people thought it more of a problem that African Americans and Latinos are “losing out because of preferences for whites” or that whites are “losing out because of preferences for blacks and Hispanics.”

Trump had the support of 34 percent of Republican-leaning voters overall, but among those who said that whites are losing out, 43 percent supported Trump. Ehrenfreund and Clement did a further analysis finding that racial anxiety was at least as important as economic anxiety — the factor most commonly associated with Trump backers — in predicting support for Trump. Though the two factors were statistically close, those “who voiced concerns about white status appeared to be even more likely to support Trump than those who said they were struggling economically.”

Other somewhat-related attributes may be as or more predictive of whether somebody will support Trump: approval of deporting undocumented immigrants, strong feelings that the government is dysfunctional, and support for banning Muslims from entering the United States. (Authoritarian child-rearing attitudes, believed by some to be closely related to Trump support, were less predictive.)

But Clement, The Post’s polling manager, told me: “What was striking to me in analyzing the data is that even after controlling for a variety of demographics and attitudes [including all those above], believing whites are losing out continued to be a key predictor of Trump support. . . . Its importance persisted under a wide range of scenarios.”

This, in turn, confirms previous findings. Earlier this year, University of California at Irvine political scientist Michael Tesler, citing data from Rand Corp.’s Presidential Election Panel Survey, found that “Trump performs best among Americans who express more resentment toward African Americans and immigrants and who tend to evaluate whites more favorably than minority groups.”

Trump’s supporters overall tend to be older, disproportionately male, less likely to have a college degree and more likely to be suffering economically. But race is an ever-present factor among Trump supporters. Trump support, it has been shown, is high in areas where the number of racist search queries on Google is also high. The Post’s Jeff Guo has documented that Trump, in GOP primaries, performs best in areas where the middle-aged white death rate is highest — that he effectively channels “white suffering into political support.”

Various polling of more dubious methodology has found that Trump supporters are more likely to support the Confederate battle flag, oppose Abraham Lincoln’s Emancipation Proclamation and support the Japanese internment camps of World War II. But Thursday’s poll by nonpartisan Pew, a well-respected outfit, finds antipathy toward minorities as well: Sixty-nine percent of Trump supporters say immigrants burden the country, and Trump supporters are significantly more likely than other Republican voters to want illegal immigrants deported, to favor a wall along the Mexican border and to support extra scrutiny of Muslims in the United States solely because of their religion.

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Some Trump supporters may not be overt about (or even conscious of) racial motivations. One indication: Trump support is higher in automated or online polls than in surveys conducted by a live interviewer — about five percentage points, according to a study by the polling firm Morning Consult. One possible factor is a “social desirability bias” that leads them to tell an interviewer not what they believe but what they think is acceptable in society.

This may mean some Trump supporters feel a sense of shame — and that’s good. Trump makes bigots feel safe to come out of the shadows. But that doesn’t excuse them.

Twitter: @Milbank

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