The remark wasn’t a new position for Biden, but the phrasing gave the president an opening to hammer his MAGA-branded attack: Trump loves fracking; Biden hates it.

“Biden confirmed his plan to abolish the entire U.S. oil industry,” Trump said Monday, speaking to supporters in Allentown, Pa., incorrectly describing Biden’s stance, which is actually focused on ending federal subsidies for fossil fuel companies, barring new fossil fuel permits on public lands and transitioning to renewable energy sources over three decades to combat climate change.

“That means no fracking, no jobs, no energy for Pennsylvania families,” Trump added, misleadingly. “He wants to go wind.”

It’s a rhetorical approach that has played well in the past with a subset of the Pennsylvania electorate, including a portion of the white working-class voters who turned their back on the Democratic Party in 2016 to help flip the state for Trump. Over the past decade, fracking boomed along the Marcellus Shale that stretches through Appalachia and Pennsylvania, becoming part of the state’s economic lifeblood. It fueled local investments from shale operators, pipeline companies and service companies that now employ thousands of Pennsylvanians with, on average, well-paying jobs.

But Trump’s full-throated fracking evangelism is not necessarily a message that appeals to the state at large — a slim majority of Pennsylvania’s registered voters opposed fracking in an August CBS poll, and nearly half of registered voters supported an outright ban in a January Franklin & Marshall College poll. And some of the energy firms that rushed to the state in recent years have seen their stocks plummet as the industry struggles.

“I don’t think there’s a fear [Biden] will ban it, but what will he do from an alternative energy front that could increase costs on our members?” said Sam Denisco, vice president of Government Affairs at the Pennsylvania Chamber of Commerce. “The traditional industries don’t want to subsidize their competitors. We could talk about who’s creating jobs, but this goes back to the traditional forces that are still here in Pennsylvania, and we’re doing great.”

With its 20 electoral votes, Pennsylvania is one of the swing states that will determine who wins the 2020 election. Trump has visited the state three times in October, holding rallies in Erie and Johnstown. Meanwhile, Biden has made four appearances in the past month, including a televised town hall in Philadelphia. Biden also dispatched his most popular surrogate, former President Barack Obama, to the state last week for his first 2020 rally.

Biden has maintained a consistent lead in Pennsylvania, with recent polling averages giving him a roughly 6-point advantage. Trump won the state by less than 1 percentage point in 2016, and has dismissed the 2020 polling data, arguing that private, internal campaign numbers look more favorable.

“I think we’ll win Pennsylvania by more than we did last time,” Trump told reporters upon landing in Allentown.

Pennsylvania is symbolically important to the political rise of both candidates.

In 2016, Trump became the first Republican presidential candidate since George H.W. Bush to break through the “blue wall” in Pennsylvania. Biden, for his part, has defined his image for years through countless stories about his roots in Scranton, a midsize city in northeast Pennsylvania.

“It may come down to Pennsylvania,” Biden told supporters on Saturday at a campaign event in Bucks County, just outside Philadelphia.

The Trump campaign’s schedule reflects that fact.

First lady Melania Trump on Tuesday will make her first-ever 2020 campaign appearance in Atglen, Pa. Former Trump adviser Kellyanne Conway will appear with the first lady, likely in an attempt to court women, a demographic that has moved away from Trump since his election.

Trump’s Pennsylvania pitch has focused largely on the economy, a complicated subject for him in the state.

On the campaign trail in 2016, Trump made bold proclamations about revitalizing the state’s manufacturing sector. While the state added manufacturing jobs in 2017 and early 2018, it has been shedding them since October 2018. And with the pandemic-driven economic decline, the state has 600,000 fewer jobs overall than when Trump took office.

More specifically, fracking supports from 20,000 to 50,000 jobs in the state, according to the Pennsylvania Department of Labor and Industry. Since 2018, though, low gas prices, which Trump touts as a positive for consumers, have hurt the fracking industry, with large companies divesting from the region.

Concerns over the environment and climate change have also driven a push to move away from fracking and fossil fuels. Carbon dioxide emissions from burning fossil fuel are a major contributor to global warming, and environmental activists have long warned that fracking also damages local resources, polluting the air and contaminating drinking water in some cases.

Still, Trump’s allies say it’s a winning issue for the president. They point to Trump's deregulation of the energy industry as a way to create more industry jobs. And they say Trump will push to expand oil and gas drilling into new domestic locations.

Lou Barletta, a former congressman from Pennsylvania who is now a Trump surrogate in the state, said that after Thursday night’s debate he started hearing from union members who were angry about Biden’s remarks.

“I was getting text messages from union members in Southeast Pennsylvania and Philadelphia, who also are dependent on these jobs,” he said when asked about how the Trump campaign sees Biden’s comments moving the needle in the state. “So i think you’re going to see a swing in votes in Philadelphia because of that.”

“Energy,” he added, “is the lifeline of Pennsylvania.”

Tim Murtaugh, the Trump campaign’s spokesperson, echoed the sentiment on a Saturday call with reporters.

“In these last 10 days, we intend to make it crystal clear to the voters of Pennsylvania and in other energy-producing states that Joe Biden is an absolute enemy of the energy industry,” he said. “He is an enemy of oil. He is an enemy of fracking.”