WASHINGTON >> President Joe Biden picked up the endorsement of the United Auto Workers today as he addressed the powerful union’s political convention.

“I’m proud to stand up here and announce that the UAW is endorsing Joe Biden for president of the United States,” said UAW president Shawn Fain after he laid out the reasons for the endorsement.

Biden, a Democrat, is pushing to sway blue-collar workers his way in critical auto-making swing states such as Michigan and Wisconsin, hoping to cut into the advantage that Republican former President Donald Trump has enjoyed with white voters who don’t have a college degree. Labor experts said that the UAW usually endorses candidates later as it has a mix of Democratic, Republican and unaffiliated voters.

“I’m honored to have your back and you have mine,” Biden said. “That’s the deal.”

Biden spoke as the union closes out a three-day gathering in Washington to chart its political priorities. It will be his first political event since Tuesday’s primary vote in New Hampshire, where Trump cemented his hold on core Republican voters with a victory and Biden scored a write-in win.

Biden frequently bills himself as the most labor-friendly leader in American history, and went so far as to turn up on a picket line with union workers at a GM parts warehouse in the Detroit area during a strike last fall.

“He heard the call and he stood up and he showed up,” Fain said of Biden’s historic picket line appearance. He drew a contrast between Biden’s pro-union efforts and Trump, who he said was anti-union.

“Donald Trump is a scab” he yelled to boos and hisses from the crowd. “Donald Trump is a billionaire and that’s who he represents.”

“This November we can stand up and elect someone who stands with us and supports our cause, or we can elect someone who will divide us and fight us every step of the way. That’s what this choice is about,” Fain said.

As recently as Monday, Fain was restrained in his comments, saying as the conference opened, “We have to make our political leaders stand up with us. Support our cause, or you will not get our endorsement.”

In his speech today, Fain said Biden had earned it.

But support for Biden among union members has varied from enthusiastic to uncertainty about whether to even vote come Election Day.

Caroline Loveless, a Waterloo, Iowa, resident and retired UAW member, said she would enthusiastically vote for Biden, recalling his appearance on a picket line during last fall’s strike. She said his appearance should remind union members that Biden is on their side.

“I hope they don’t get amnesia,” Loveless said, “come Election Day.”

William Louis, of Groton, Connecticut, another member, said that while he is “fed up with politicians” he will reluctantly vote for Biden, though he said the president had not fully earned members’ vote given the current state of the economy.

Louis said Biden would get his vote because Trump, the likely Republican nominee, “was a terrible president.”

Leo Carrillo, a member from Kansas City, said Biden’s appearance on the picket line showed that “he was there for us,” and helped him to decide to vote for Biden in November.

“For me it meant a lot” that a sitting president would show that level of solidarity to autoworkers, Carrillo said. “But there’s more work to be done,” he said, pointing to the PRO Act — proposed legislation that would make it easier to unionize on a federal level. The legislation advanced to the U.S. Senate but does not have enough support to survive in case of a filibuster.

Biden could run into dissent, however, over his support for Israel in its war on Hamas in Gaza. Some younger members of the union were less enthusiastic about the president for that reason.

Johannah King-Slutzky, a Columbia University graduate student and member of the student workers union within the UAW, was one of several attendees who chanted “ceasefire now” during Fain’s afternoon speech Monday. The union called for a ceasefire in Gaza in December.

“Right now he’s done nothing to earn my vote,” King-Slutzky said, because “he has not acted with urgency to stop the genocide in Gaza.”

The union has a lengthy process to determine its endorsements that involves the rank-and-file, but it’s unclear how far along that is.

Fain, the first UAW president directly elected by members, took office after a huge bribery and embezzlement scandal that ended with two union presidents serving prison time. So he’s making sure to follow union procedures on the endorsement and show that members made the decision, even though there’s no way the UAW would back Trump, said Brian Rothenberg, a former union spokesman.

The UAW, with roughly 380,000 members, is normally one of the last unions to endorse presidential candidates, Rothenberg said. For example, the union didn’t endorse Biden in 2020 until April 21.

In a November interview with The Associated Press, Fain made clear that he personally supports Biden, as he railed against Trump.

Fain pointed to Biden’s trip to the GM parts warehouse, which is believed to be the first time a sitting president appeared with union picketers.

About that same time, Trump held a rally at a nonunion auto parts maker near Detroit, which Fain said was odd. Biden’s administration also supported the union’s bid to persuade Stellantis to reopen a shuttered plant in Belvidere, Illinois, and joined Fain in the city 70 miles (113 kilometers) northwest of Chicago to celebrate its reopening, Fain said.

Trump, Fain said, didn’t travel to Detroit when the UAW was on strike while he was president in 2019, and he talked about moving auto jobs to southern states where pay is lower.

“Actions speak louder than words,” Fain said. “But this process belongs to the membership, and we’ll make those decisions when it’s time.”

Art Wheaton, director of labor studies at Cornell University, said he would be surprised to see the union endorse Biden at this point in the campaign. The UAW, he said, would hold more leverage over legislation and other items if it waits until closer to the election to announce who it’s backing.

“There’s no big hurry in terms of the UAW and their timeframe,” he said.

Rothenberg said a union endorsement is important because polling shows many UAW members are often undecided in the spring before a presidential election.

Internal UAW polling typically shows that in the spring and early summer, 30% of members support the GOP, 30% support Democrats and the remaining 40% swing between parties, he said. By Election Day, members and UAW retirees usually vote 60% Democratic, said Rothenberg, now a public relations consultant in Columbus, Ohio.

The endorsement also could sway nonunion blue-collar white males, who have been voting more for Republicans than in the past, Rothenberg said.

Associated Press writer Zeke Miller contributed to this report. Krisher reported from Detroit.