President Joe Biden is set to join members of the United Auto Workers union Tuesday in Wayne County, Michigan, walking the picket line on the eve of a visit from former President Donald Trump.

The trip comes as Biden faces consistently low polling numbers on his handling of economic issues, and, back in Washington, the looming threat of a government shutdown this week. Both a prolonged strike and a shutdown could have economic consequences – something the White House is seeking to avoid as Biden tries to convince voters his economic policies are working. He’s also appearing in the battleground state of Michigan just one day before his chief political rival – whom he defeated in the 2020 presidential election – comes to the crucial swing state to make his own appeal to union workers.

Trump, the front-runner in the GOP presidential primary race, is scheduled to skip the second Republican debate to deliver a prime-time speech to an audience of current and former union members, including from the UAW, in Detroit on Wednesday. Trump has slammed the president for the visit, claiming Biden “had no intention” of walking the picket line until Trump said he would make a speech in Michigan.