When Jim DePoe pitches fellow Pennsylvania union members on Joe Biden, he tries to assure the skeptics that Biden would not ban hydraulic fracturing, or fracking.

Often, DePoe says, the members don’t believe him.

They tell him President Trump says the Democratic nominee would end fracking, a move many fear would kill good union jobs.

“People are unfamiliar with Joe Biden’s fracking plan,” said DePoe, vice president of the International Brotherhood of Electrical Workers Local 29. “They listen to the president’s plan.”

Days before the election, Biden is fighting to protect his narrow Pennsylvania lead in the face of Trump’s relentless attacks over fracking, an economic and cultural touchstone across Western Pennsylvania that has become a vulnerability for the former vice president, according to interviews with local officials.

Tensions flared at the final debate Thursday night, with Biden asserting that he never said he opposed fracking and angrily rebuking the president’s claim that there was video evidence that he had. And conservatives seized on Biden’s comment that he would “transition from the oil industry,” which he later sought to underscore would happen gradually.

Biden has been warmer toward fracking than many in his party, assuming a stance his team hoped would neutralize attacks from the right. His position helped him secure endorsements from a roster of influential labor unions, including two that joined him on a recent whistle-stop train tour through the region.

But their support is not always trickling down to union members themselves. Local leaders say Biden’s occasionally muddled message on fracking, combined with Trump’s broadsides and suspicion about the Democratic Party’s energy and climate priorities, has created obstacles for the former vice president.

“I would say it’s a 50-50 split in membership of who’s supporting who,” said Keith Thurner, business manager of the International Union of Operating Engineers Local 95, speaking of his Pittsburgh-based branch. “Even though International has endorsed Joe Biden, we have stepped back from that. We let the membership know what the International does. But there’s so many undecideds or folks on either side.”

The IUOE endorsed Biden last month, and officials joined his whistle-stop tour. The international union includes many members who work on pipelines and other gas projects.

In the final leg of the Pennsylvania race, Biden and many of his union allies are not emphasizing fracking, focusing instead on broader economic themes and capitalizing on anger with Trump’s handling of the coronavirus pandemic, wagering those factors will offset any goodwill for the president on energy matters.

But in many cases, officials said, union members bring up fracking on their own as they mull their decisions, prompting an urgent push to address their anxieties through one-on-one conversations and other contacts. To many, it’s an argument over who has the backs of blue-collar workers.

“It’s about their jobs, you know?” said Rep. Conor Lamb (D-Pa.), a close Biden ally whose district stretches from suburban Pittsburgh to the Ohio border.

Four years ago, many union members flouted the recommendations of national leaders and voted for Trump over Hillary Clinton, whose comments about coal and energy rubbed them the wrong way. While local officials say they see signs of eroding support for the president in their unions, there remain pockets of enthusiasm for Trump.

Pennsylvania is second only to Texas in natural gas production, and fracking is a controversial natural gas extraction technique. Environmentalists have voiced worries about greenhouse gas emissions and water pollution associated with fracking. Advocates cite the jobs it has created in the gas, electricity and construction business.

Fracking has taken on an outsize importance in Western Pennsylvania because of its effect on a range of related industries, officials said. Lamb noted that in his district, a massive construction project is underway to create a petrochemicals complex that will turn a natural gas byproduct into plastic pellets used in manufacturing. It has created jobs for electrical workers, builders and others. Trump has sought to claim credit for the plant, even as it was announced during the Obama administration.

Lamb said that combating Trump’s message on fracking has “been a big challenge,” adding that earlier this year, he “was getting calls and running into people out in the community who were telling me how big of a deal this was.”

A large part of the challenge, local union leaders say, is Biden’s position is nuanced, and he hasn’t always explained it clearly.

Biden does not support a ban on fracking, a position that sets him apart from liberals like Rep. Alexandria Ocasio-Cortez (D-N.Y.), who are advocating a sweeping “Green New Deal” to tackle climate change. But he has called for safely managing it, as well as an end to new permits for drilling on federal lands, which account for a small fraction of oil and gas wells.

During the final Democratic primary debate, Sen. Bernie Sanders (I-Vt.) touted his opposition to fracking, prompting Biden to flex his own environmental credentials. “No new fracking,” he declared. Climate activists hailed his comments. But his campaign to clarify that his position hadn’t changed.

Still, Biden’s words would later end up in a Trump ad.

With the primary behind him, Biden has spoken more forcefully about his position. “I do not propose banning fracking,” he said in a recent ABC News town hall. “I am not banning fracking,” he said in a late August speech in Pittsburgh, which was mostly focused on denouncing political violence.

In Thursday’s debate, Biden repeated himself, saying, “I have never said I oppose fracking.”

“You said it on tape,” Trump interjected.

“Show the tape,” Biden challenged him angrily. Asked if he was ruling out a fracking ban, Biden said he was.

Even so, the Trump campaign has repeatedly, if inaccurately, claimed that Biden would end all fracking if elected president. At a campaign rally Tuesday night in Erie, Pa., Trump played selectively edited clips of Biden. “To all the people of Pennsylvania, hear this warning: If Biden’s elected, he will wipe out your energy industry,” Trump declared. “Only by voting for me, can you save your fracking in Pennsylvania.”

Unlike Biden, who has advocated ambitious action to combat climate change, such as a vow to eliminate carbon pollution from power plants by 2035, Trump is running as an unapologetic champion of fossil fuels and has questioned whether climate change is real. He has pulled the United States out of the Paris climate accord that Biden has pledged to reenter.

“Would you close down the oil industry?” Trump asked Biden in the debate.

“I would transition from the oil industry, yes,” Biden said.

After the debate, Biden tried to minimize hostilities toward the oil business, saying he was talking about gradual move. “We’re getting rid of the subsidies for fossil fuels, but we’re not getting rid of fossil fuels for a long time,” he told reporters.

Biden’s campaign has sought to combat Republican attacks with digital ads challenging Trump’s false claims. His team is more invested, however, in touting his broader economic message, which aides feel will resonate with working class voters in Pennsylvania. His “Build Back Better” proposal would make massive investments in domestic manufacturing and jobs.

Many pro-Biden industrial unions are waging urgent pushes to secure the support of members through a flurry of conversations, texts, mail and other outreach designed to persuade them that Biden is a better ally for workers than Trump. Like Biden, they are often underscoring issues other than fracking.

The United Brotherhood of Carpenters and Joiners of America endorsed Biden last months and the union’s final mail piece, landing in Pennsylvania this week, makes no mention of fracking. On one side are photographs of workers in hard hats and goggles. On the other, it says Biden takes the pandemic seriously and opposes efforts to weaken unions.

On the whole, local and national union organizers say Biden has made a much stronger argument to workers than Clinton did. Her declaration that “we’re going to put a lot of coal miners and coal companies out of business,” still haunts some officials. They feel it alienated White working-class voters in the state, who turned to Trump and his promises to be their champion and revive flagging industries.

Biden has other advantages over Clinton, too. From the outset of his campaign, he sensed an opportunity to build inroads with powerful unions that were looking for a candidate who was not as hostile to the energy industry as other contenders in the race. A moderate Democrat with humble roots in Scranton, he looked and talked the part of someone who steamfitters and electrical workers could grab a beer with after work.

“When we were designing the vice president’s climate agenda, the first question he asked was, ‘What does the science say we need to do in order to stop the worst impacts of climate change?’” said Stef Feldman, Biden’s policy director. “And then we worked backward to achieve that end, to figure out the best way to do that and preserve and create good union jobs and grow our economy.”

Biden made himself accessible to union leaders, and his team invited their input as they crafted policies such as “Build Back Better.”

“I spoke to him personally about some of our concerns,” said Lonnie Stephenson, the president of the International Brotherhood of Electrical Workers. “He was the first candidate to really openly reach out to us and to labor and to want us to be at the table.”

In February, IBEW endorsed Biden — a full four months earlier in the campaign than they backed Clinton in 2016.

Biden’s campaign has taken other steps to shore up support from union voters in Pennsylvania. His campaign added Lamb to a joint climate change task force with the Sanders campaign that convened earlier this year and included Ocasio-Cortez. And Biden asked Lamb for advice the day after his first debate with Trump, Lamb said. The congressman said he stressed to Biden the importance of the endorsement he was receiving that day from the Carpenters and Joiners and the IUOE.

In Erie County, Pa. — a swing county in a battleground state — officials are trying to navigate the challenges of holding an election during a pandemic. (The Washington Post)

The Laborers’ International Union of North America, which has significant membership working in natural gas and related industries, has talked to members and sent them mail in an effort to rally support for Biden, according to Philip Ameris, the president of the Laborers’ District Council of Western Pennsylvania. When it comes to fracking, “The messaging we had to get out was ‘Look, you can’t listen to the sound bites, you’ve got to take the real news.’ ”

“There’s a lot of our members that support Trump,” he added.

Christine Spolar in Pittsburgh contributed to this report.