The United Auto Workers has endorsed Vice President Kamala Harris over Republican presidential nominee and former President Donald Trump.

The union’s endorsement shouldn’t be surprising. UAW President Shawn Fain has been outspoken against Trump. The Detroit union also has historically supported Democrats, including President Joe Biden.

It comes after Biden withdrew his re-election bid and endorsed Harris to become the Democratic nominee against Trump.

Fain and Trump have been at odds — publicly trading remarks — since the union leader was elected early last year. Trump called for Fain to be fired during a speech earlier this month at the Republican National Convention.

The union responded with a post calling Trump a “scab and a billionaire,” continuing “that’s who he represents. We know which side we’re on. Not his.”

Quickly after Biden dropped out of the election, the UAW praised him and showed support for Harris, who walked a picket line with union members during a strike in 2019.

“The path forward is clear: we will defeat Donald Trump and his billionaire agenda and elect a champion for the working class to the highest office in this country,” the union said in a statement July 21 after Biden had dropped out of the 2024 race. That statement stopped short of formally endorsing Harris.

The UAW’s endorsement is crucial for any candidate looking to secure the battleground state of Michigan, because of the UAW’s potential influence there. The Detroit-based union has roughly 370,000 active members and 580,000 retired members, many of which reside in the Midwest.

Michigan voters helped both Biden and Trump to win the White House during the past two presidential elections.