(Bloomberg) -- President Joe Biden dismissed Republican frontrunner Donald Trump’s attacks on his push for electric vehicles in a fight between the 2024 contenders over support from organized labor.

“This guy, the argument he’s making now about autoworkers is ‘Biden’s your problem because Biden wants to have electric vehicles,’” Biden said Thursday, making the sign of the cross, at a fundraiser for his reelection campaign in Phoenix.

Biden knocked Trump for delivering a speech at a nonunion auto supplier in Michigan while union members of the United Auto Workers are striking against Detroit’s Big Three legacy automakers.

“The idea he goes to a union hall — not a union hall, it’s management — and he pays them to hold up signs saying they’re union members? Come on,” Biden said. 

Both Biden and Trump this week made visits to Michigan to woo blue-collar voters amid a UAW strike against General Motors Co., Ford Motor Co. and Stellantis NV. The dueling visited highlighted how the labor dispute and battle for union support have become a 2024 campaign flashpoint.

Biden visited a picket line outside a GM plant in suburban Detroit on Tuesday, telling striking workers to “stick with it,” and endorsing the union’s demands for a major wage increase. The strike is centered on benefits, representation and Biden’s own clean-energy push, which labor leaders and autoworkers worry will mean fewer jobs at union facilities and lower wages.

Trump on Wednesday skipped the second Republican presidential debate and spoke to an invitation-only crowd on the shop floor of Drake Enterprises, a nonunion supplier of parts, in Michigan.

Trump and fellow Republicans have assailed Biden’s clean-energy push, saying the EV transition will saddle US consumers with higher car costs and cost US autoworker jobs.

“You can be loyal to American labor or you can be loyal to the environmental lunatics. But you can’t really be loyal to both, it’s one or the other,” Trump said Wednesday night. The former president also attacked GM and Ford for not doing more to resist Biden’s EV policies.

Trump had announced his trip to Michigan before Biden’s as he seeks chip away at support from organized labor — a crucial bloc in the president’s electoral coalition. Trump has also sought to drive a wedge between union leaders who have historically backed Democrats and rank-and-file members who include Republicans.

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