The Times first asked donors why they decided to donate to the mayor; for those who didn’t immediately hang up, a second question followed: Do you think he should be president?

Out of 35 people who stayed on the line long enough to hear the question, five said yes — including a lawyer in Pennsylvania, an architect in Brooklyn and a woman on the Upper East Side. Seven said no, and the rest either expressed no preference or declined to say.

Alex Tourk, a San Francisco public relations executive who gave $5,000 in September, had kind words for Mr. de Blasio. But as a presidential candidate? “I am supporting Senator Kamala Harris,” he said.

Several less well-heeled donors said they had given to Mr. de Blasio’s committee not so much out of personal support for the mayor’s mission, but because of interpersonal ties in particular immigrant communities.

Donations to Fairness PAC clustered around a handful of such events: one fund-raiser last year in Queens drew many Asian-American donors; another tapped into bonds in an Indian-American community on Long Island.

An event in March saw a large number of Albanians gather for the mayor in a private room at Joseph’s Italian restaurant in Lower Manhattan. The host, Ilirjan Rusi, said the event attracted a range of small business people, restaurateurs and those who work in the building trades. “The Albanians like the photo ops!” he said, laughing.

(That night’s haul may have been offset by Mr. Rusi’s brother, Selim, a longtime supporter of Mr. de Blasio’s: Records show that a month earlier he had donated $41,000 to President Trump’s re-election.)