A 2015 rally marked the 20th anniversary of the Million Man March. (Photo: Evan Vucci/AP)

WASHINGTON — Republican attitudes toward African-Americans hardened significantly in 2016, according to an authoritative new study.

Only 32 percent of self-identified Republicans in 2016 said they believe that African-Americans face “a lot of discrimination.” That was a significant drop from just a year earlier, when the Public Religion Research Institute asked the same question. In that survey, 46 percent of Republicans responded that blacks experience significant discrimination.

In fact, more than half of Republicans told PRRI in 2016 that “discrimination against whites has become as big a problem as discrimination against blacks and other minorities.” Among Democrats, 69 percent disagreed with this statement, and 59 percent of independents disagreed.

The 2016 study surveyed 40,509 people by phone in the second half of the year, starting in mid-May, just after Donald Trump had effectively clinched the GOP nomination.

About three-quarters of self-identified Republicans are white Americans who identify as Christian, said PRRI CEO Robert P. Jones.

Attitudes among voters of other political persuasions stayed fairly steady on the question of discrimination against African-Americans during this period. Among independents, 58 percent said in 2016 that blacks are discriminated against, a drop of just 1 point. And 77 percent of Democrats answered affirmatively in 2016, down just 3 points from a year earlier.

When PRRI first asked the question in its 2015 study, public awareness of the Black Lives Matter movement was still growing. Since then, there have been a number of other well-publicized cases of blacks killed by police under questionable circumstances.

Jones noted that Trump’s campaign in 2016 included “a very hard pushback to Black Lives Matter … that began to be seen as the Republican response.”

Trump called the group a “threat” and said that “a lot of people feel that it is inherently racist.”

“It’s a very divisive term, because all lives matter. It’s a very, very divisive term,” Trump said.

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The phrase “blue lives matter,” intended to signal support for the police, became a rallying cry at the Republican Convention in Cleveland last year, after eight police officers were shot and killed in separate incidents in Dallas and Baton Rouge.

But in the weeks leading up to the convention, Trump also condemned the fatal shooting of two black men by police officers: Alton Sterling in Baton Rouge, La., on July 5 and Philando Castile in St. Paul, Minn., the next day.

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Protesters carry a banner depicting Philando Castile on June 16 in St Paul, Minn. (Photo: Stephen Maturen/Getty Images)

The officer who shot Castile during a traffic stop was acquitted of all charges earlier this month.

“I thought they were horrible, horrible to witness,” Trump said at the time. “Whether that’s a lack of training or whatever, but I thought they were two incidents that were absolutely horrible to witness. At the same time, our country is losing its spirit. African-Americans are absolutely losing their spirit.”

Sterling and Castile are just two of the many black men and women who have died from police shootings or in custody, often in incidents that have been captured on video and released to the public. The list from 2014 to 2016 includes Michael Brown, Laquan McDonald, Tamir Rice, Eric Garner, Walter Scott, Freddie Gray, Sandra Bland, Joseph Mann, Paul O’Neal, Terence Crutcher, Keith Lamont Scott and several others.

Jones said the different partisan and racial attitudes about discrimination mirror long-standing trends in American life. He also believes that the significant change in Republican attitudes between 2015 and 2016 indicated that the presidential campaign — and the amount of attention and discussion it focused on the topic — had a substantial impact.

“Presidential campaigns are fairly influential in terms of what they signal to people … what they highlight and don’t highlight,” Jones said. “They send cues to people.”

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