General Motors assembly workers picket outside the General Motors Powertrain Flint Engine plant during the United Auto Workers (UAW) national strike in Flint, Michigan, U.S., September 16, 2019.

A strike by nearly 50,000 autoworkers has Democrats in key 2020 races jumping not only to show their support for a key constituency but also to put pressure on President Donald Trump in a battleground state.

United Auto Workers members went on strike starting late Sunday as the union failed to reach a deal with General Motors. Workers set up picket lines at dozens of plants and parts warehouses around the country. Talks picked up again Monday morning as the sides try to resolve differences over benefits and wages.

Democrats running to challenge Trump next year — from Sens. Bernie Sanders, I-Vt., and Cory Booker, D-N.J., to South Bend, Ind. Mayor Pete Buttigieg — raced to show solidarity with the autoworkers. Though unions have lost political strength in recent years, the party still views their support as a key step in winning over working-class voters.

Some officials also cited the strike in arguing Trump has failed to follow through on promises to Midwestern voters to protect manufacturing jobs and stop outsourcing. A prolonged strike could create particular intrigue in Michigan — GM's home state and an area Trump won by a mere 11,000 votes in 2016.

"It's clear that this administration doesn't have a manufacturing policy whatsoever. There's no strategy to keep jobs in the United States," Sen. Gary Peters, a Michigan Democrat who faces a competitive reelection bid next year, told MSNBC on Monday morning.

Trump carried Michigan, Wisconsin and Pennsylvania in 2016 in part by promising to overhaul trade deals that he says sapped U.S. manufacturing jobs. While he has blasted unions as "dues sucking" organizations, he outperformed recent Republican presidential candidates among union households in 2016.

The president issued only a brief tweeted comment about the strike on Sunday.

"Here we go again with General Motors and the United Auto Workers," Trump wrote. "Get together and make a deal!"

Trump tweet

The White House and Trump campaign did not immediately comment further on the work stoppage.

Trump's message on the strike took a decidedly different tone than those from the Democrats who aim to deny him a second term in the White House. Multiple Democratic primary contenders, including former Vice President Joe Biden and Sen. Elizabeth Warren, D-Mass., put out statements backing the autoworkers.

The candidates praised the workers for going on strike — as they have done repeatedly this year during work stoppages as they vie for support from organized labor. They also took swings at GM, continuing a trend of criticizing companies for what they call putting profits over workers.

"I am proud to support the UAW workers who are standing up to the greed of GM," Sanders said in a tweeted statement Sunday.

Sanders tweet

Warren tweeted Sunday that she stands with the union workers as "they strike to get what they deserve." She pushed "GM to come to the table and negotiate in good faith."

Warren tweet

Biden also wrote that he is "proud to stand with UAW to demand fair wages and benefits for their members." He added that "America's workers deserve better."

In a statement Sunday, GM defended its latest offer to the UAW. The company called it a "strong offer that improves" wages and benefits and "grows U.S. jobs in substantive ways." The automaker said the plan included more than $7 billion in investments, including possible uses for factories in Michigan and Ohio where it recently stopped production.

GM also said the proposal included wage hikes or lump sum pay increases in all of the four years it would cover. The company did not immediately respond to a request for comment on the criticism from Sanders and other Democrats.

The use of temporary workers, who generally receive lower pay and lighter benefits, has reportedly tripped up negotiations.

The strike comes at a delicate time for the UAW, which counts more than 400,000 people among its active members. The negotiations are taking place after federal prosecutors charged UAW Region 5 Director Vance Pearson with helping to conspire to steal dues. Officials also reportedly implicated UAW President Gary Jones, though he has not been charged with any wrongdoing.

Most Democrats backing the strike took care to praise the individual members of UAW rather than the organization itself.

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