Donald Trump talked up his appeal to labor groups in hotly contested Erie County Saturday evening, a western Pennsylvania bellwether Joe Biden won by a razor-thin margin almost three years ago.

Known for its labor union roots, Erie County is emblematic of the ongoing battle for organized labor ahead of next year’s election, particularly if the country sees another Biden-Trump rematch. Trump, who won the support of many rank-and-file union members seven years ago, is currently vying for an endorsement from the United Auto Workers union.

UAW’s president Shawn Fain has criticized the Biden administration for pumping out billions in subsidies for electric vehicles without requiring higher wages and other protections. The union has so far withheld its support from Biden, frustrating current and former Biden aides.

Alongside slamming the Biden administration’s green energy policies, Trump on Saturday spoke about his attempt to win over workers to his — and the GOP’s — cause.

“Don’t forget the Democrats start off with a big advantage, they think they have the unions,” he said. “I happen to think the unions, the workers … we have a lot of the people in the unions with us. I think we have largely a majority. You’ve got to win that whole East Coast.”

Trump’s campaign stop marked his second trip to the state in a month, after Biden held his first political event of his reelection bid in June with a union rally in his regular haunt of Philadelphia. Labor groups, including the AFL-CIO, threw their support behind the president last month, with the AFL-CIO noting that it was the earliest in a presidential cycle that the group had endorsed a presidential candidate. Biden often calls himself the most “pro-union” president and a son of Scranton, Pa.

In 2020, Erie was one of two of Pennsylvania’s 67 counties that flipped from Trump to Biden. The city of Erie, its suburbs and rural pockets have played a pivotal role in determining which direction the state goes. Erie’s surrounding county voted for President Barack Obama twice before Hillary Clinton lost the county by fewer than 2,000 votes.

On Saturday, Trump slammed Washington’s “betrayal of workers … particularly in Pennsylvania.” He talked up his administration’s enactment of the USMCA trade deal to replace NAFTA.

He further touted his administration’s economic policies including tariffs on steel. “It’s the economy, stupid,” he said, echoing Bill Clinton’s famous election mantra in what he said could be the defining issue of the 2024 election.

“Since Joe Biden took over, he has wrecked our economy,” he added, before citing a litany of economic factors he claimed were in his previous administration’s favor, including worker productivity.

“I will defend Pennsylvania energy jobs including fracking,” he added to cheers. “We want American workers working.”

But Trump’s focus was fleeting. His speech was combative, largely focused on his own legal troubles, attacking his rivals for the GOP presidential nomination and relitigating his 2020 election loss.

In perhaps the most notable moment, Trump called on congressional Republicans to withhold military support to Ukraine “until the FBI, DOJ and IRS hand over every scrap of evidence they have on the Biden Crime Family’s corrupt business dealings.”

The language echoed his demands as president that Ukraine announce an investigation into the Bidens, which spurred his first impeachment.

Democrats on Saturday were out in full force ahead of Trump’s rally, a preview of the contentious 2024 battle set to play out in the key swing state. In 2020, Biden won Pennsylvania by just 1.2 percentage points, and Erie County by 1,400 votes, a small margin that Trump — if he manages to secure the GOP nomination — is working to turn back in his favor.

The DNC announced a new five-figure digital ad buy in the battleground state on Saturday, contrasting “Trump’s countless unfulfilled promises” with Biden’s record on job creation, infrastructure and health care. The ad, titled “Trump talks. Biden delivers,” shows a split-screen of the former and current presidents.

“As Trump takes his lies to Pennsylvania and across the country, the DNC will constantly remind voters of the stark differences between Trump’s abysmal economic agenda and the numerous accomplishments President Biden has delivered for working families,” DNC chair Jaime Harrison said in a statement.

The AFL-CIO’s secretary-treasurer, Fred Redmond, and T.J. Sandell, of Erie, a union plumber with Plumbers Local 27 and president of the Great Lakes Building and Construction Trades Council, accused the former president of having an “anti-worker record,” on a Saturday morning press call as Trump continues to make a play for organized labor, most recently vying for an endorsement from the United Auto Workers.

“Donald Trump doesn’t care about workers. Trump undermined workers’ rights. Trump rolled back workplace safety rules. He delivered massive tax giveaways to the extremely rich and big corporations while not lifting a finger to help struggling working people in Erie and so many other communities around the country,” Redmond said.

Trump’s event at Erie Insurance Arena comes just days after federal prosecutors rolled out additional charges against the former president in the classified documents case. In a separate investigation, special counsel Jack Smith’s team also appears to be on the verge of indicting him for efforts to subvert the results of the 2020 election in several states, including in Pennsylvania.