The Teamsters Union caused a stir Wednesday by releasing internal polling that found former President Donald Trump leading Harris nearly two-to-one among its members. The union subsequently declined to issue an endorsement, the first time it had not backed the Democratic presidential ticket since 1996.

“Rank-and-file union workers like the Teamsters relate to Trump, a builder who has worked with many unions, to a person who has never created working-class jobs,” Dan Bowling, who teaches labor courses at Georgia State University, told the Washington Examiner.

What may be even more worrying for Democrats is the shift in the support after Biden left the race. Rank-and-file Teamsters backed Biden over Trump 44.3% to 36.3%, according to the union’s own polling, but two polls taken after Biden dropped out found Trump taking nearly 60% of the vote, with Harris polling in the low 30s.

Among the wider electorate, Harris’s numbers are vastly superior to Biden’s. She has pulled ahead in national polling averages after he trailed badly for most of the year. But blue-collar, noncollege-educated workers make up a notable voting bloc of the midwestern blue wall states of Wisconsin, Michigan, and Pennsylvania, which will be crucial in deciding the election.

Trump’s campaign says it is a strong signal for the former president.

“Workers know Kamala Harris — and her support for a fracking ban, electric vehicle mandate, and other Radical Left lunacy — would be devastating,” Trump’s campaign said in a Wednesday statement. “President Trump has always had the backs of American workers — and always will.”

The Teamsters union represents a largely male workforce of truckers, rail workers, and UPS drivers and has a historic independent streak. The group endorsed Richard Nixon, Ronald Reagan, and George H.W. Bush before turning toward Democrats in the 1990s, and it is the only major non-law enforcement union that has not backed Harris this year.

Still, the news represents a blow to Harris and possibly a turning point in the identity of both major political parties. Trump has heavily courted union voters this cycle, promising that fracking bans and electric vehicle mandates would gut energy jobs in Pennsylvania and wreck the auto industry in Michigan. Trump’s running mate, Sen. J.D. Vance (R-OH), walked a picket line with the United Auto Workers last year.

According to a new Trump campaign ad, Harris wants to “end all gas-powered cars.”

#Election2024: “Kamala Harris wants to end all gas powered cars…Michigan auto workers are paying the price. Massive layoffs already started. You could be next.”

The Trump campaign is up with this new ad in #MIPol. Future Presidential reservations in #MIPol:
🔵$56.5m🔴$34.0m pic.twitter.com/Wxcip9sWp5

— AdImpact Politics (@AdImpact_Pol) September 19, 2024

The Harris campaign says union voters will back her, pointing to endorsements from local Teamsters groups and her own history of joining picket lines.

“The vice president’s strong union record is why Teamsters locals across the country have already endorsed her — alongside the overwhelming majority of organized labor,” Harris spokeswoman Lauren Hitt said. “As the vice president told the Teamsters on Monday, when she is elected president, she will look out for the Teamsters rank-and-file no matter what.”

A New York Times poll of Pennsylvania voters found that Harris is leading Trump 50% to 46% in the commonwealth. However, Trump led by 13 points with men, and by 27 points with white, noncollege voters. Harris’s support had also slipped relative to Biden among Black and Hispanic voters.

Democratic strategist Brad Bannon told the Washington Examiner that the Teamsters are an exception to the rule and that most union voters continue to back Harris. Even so, he said blue-collar workers are especially concerned about inflation and need to hear more from her on that topic.

“The No. 1 issue in all of those [swing] states is inflation,” Bannon said. “I would advise the vice president to be very aggressive talking about inflation.”

And even if Harris costs Democrats with some union voters, Rep. Dan Kildee (D-MI) says she is the only person who can win the White House for his party.

“If we have a shot to win this election, it’s with Kamala Harris,” he told the Washington Examiner. “Fair or not, we were not in a position with President Biden leading the ticket to be able to compete the way we are now.”

Kildee stressed that union voters are not monolithic but said the Democratic Party has done more to support them over the years.

“Despite the fact that many of the members of that union [the Teamsters] don’t vote for Democrats, Democrats didn’t say, ‘We’re going to let your pension implode,’” Kildee said. “We feel like the pension is a promise. When Donald Trump was president, he had four years to fix the problems in those pension systems. He didn’t do a thing.”

Biden directed $36 billion to a Teamsters pension fund in 2022, the largest private pension bailout in American history.

Republican strategist John Feehery told the Washington Examiner that the Teamsters poll represents an opportunity for Republicans, but it will only matter if they can capitalize by turning the support into actual votes.

“Get them out to vote,” he said. “Turnout is key in this election, and we need to make sure we are organized enough to get organized labor out to vote for us.”

Marisa Schultz contributed to this report.