“I don’t remember any remarks he ever made that was not sharing with me how much he thought about himself,” he said. “It was always the same story.”

The Rev. Al Sharpton, the civil rights leader who has grown more publicly critical of Mr. Trump in recent years, likewise recalled nothing overt. “I’ve never heard him say anything racial,” he said. But, he added, “I always sensed he was not comfortable being around us. He reminded me what he was — a Queens guy. He saw us as entertainers or athletes that he had to do business with.”

When Mr. Trump opened Mar-a-Lago as a club in the 1990s, he welcomed African-American and Jewish members. Still, he did not mind turning societal divisions to his advantage, at one point claiming Palm Beach was anti-Semitic in a zoning dispute because his members would be Jewish.

‘Put People in These Boxes’

Some who worked for Mr. Trump said he showed his true colors after growing comfortable with people. Jack O’Donnell, who was president of the Trump Plaza Hotel and Casino and later wrote a scathing book about Mr. Trump, said the mogul would come into the casino and notice many African-Americans. “It’s a little dark tonight,” he would say.

According to Mr. O’Donnell, Mr. Trump said “laziness is a trait in blacks” and complained about an African-American accountant: “Black guys counting my money! I hate it. The only kind of people I want counting my money are short guys that wear yarmulkes every day.”

In an interview, Mr. O’Donnell said Mr. Trump trafficked in stereotypes. “He genuinely believes things like white people are smarter. And black people don’t want to live next to white, and white people don’t want to live next to black people,” Mr. O’Donnell said. “And he rationalizes that as, everybody thinks that, so it’s not racist.”

Mr. Trump has dismissed Mr. O’Donnell as “a loser” but at one point accepted the book’s description. “The stuff O’Donnell wrote about me is probably true,” he told Playboy. Later he disputed Mr. O’Donnell’s account, telling NBC’s “Meet the Press” that “he made up stuff.”