Still, Mr. Fain has not said whether the U.A.W. will officially endorse Mr. Biden. Representatives for the union and the Biden campaign had no comment on Wednesday about whether the endorsement would come. Mr. Biden, who calls himself the “most pro-union president in history” and was the first sitting president to visit a picket line, has appeared at several U.A.W. events to prove his bona fides with the group’s leadership and rank and file.
“I’ve been involved in the U.A.W. longer than you’ve been alive,” Mr. Biden, then 80, told the boisterous crowd at an event in Illinois in November, after the union reached an agreement with Ford, General Motors and Stellantis on a contract that included pay increases and reopened a plant in Belvidere, Ill.
At that event, he castigated Mr. Trump for insisting that electric vehicles would lead to the loss of thousands of manufacturing jobs.
“Well, like almost everything else he said, he’s wrong,” Mr. Biden said at the time. “And you have proved him wrong. Instead of lower wages, you won record gains. Instead of fewer jobs, you won a commitment for thousands of more jobs.”