LEHIGHTON, Pennsylvania — Linda Christman looked across the Pohopoco Creek and traced a line from the crest of a ridge, down the wooded slope, beneath the rippling water, and up again through Beltzville State Park, where ospreys nest along the shore.

This is one part of the proposed path of the 120-mile PennEast Pipeline, which is designed to deliver gas from booming fracking fields in the northeast of Pennsylvania.

Campaigners against the pipeline, like Christman, fear construction will leave a 50-foot swath of dead space running through the forest, a brown, barren strip across the state.

“If the vegetation is stripped back, it will turn the whole thing into a gully and all the silt will run down,” threatening to clog the creek and destroy its biodiversity, she said.

The activists may be focused on local concerns — the 87 waterways, 53 wetlands, and 33 parks they say are at risk of destruction — but the wrangling is a microcosm of the national debate over energy policy and one that Trump campaign officials believe they can use to their advantage.

It pits business groups and unions — that see a $1.6 billion windfall for the regional economy and the creation of an estimated 12,160 jobs — against environmental groups.

And therein lies a problem for a candidate like former Vice President Joe Biden should he become the Democratic nominee. Opponents believe they can weaponize the issue of fracking and energy to separate him from his blue-collar, union allies after a series of promises to move against fracking.

Kelly Sadler, of the pro-Trump nonprofit America First Policies, said the greenward shift in the Democratic Party threatened 10 million jobs that were supported by the oil and gas industries.

“Joe Biden is taking an extremist position in saying he wants to ban fossil fuels and crack down on fracking, which has brought great prosperity to places like Pennsylvania. Not only that, fracking has led to stability in the world energy markets and we are now the number one exporter of natural gas."

In the July 31 Democratic debate, Biden promised there would be no place for fossil fuels, including coal and fracking, if he became president.

“We would make sure it’s eliminated and no more subsidies for either one of those, either — any fossil fuel,” he said.

On other occasions, he has stopped short of demanding an end to fracking but has joined most other Democratic 2020 candidates in endorsing the goal of the United States reaching net-zero emissions by 2050.

David Urban, who served as a senior adviser to the Trump 2016 campaign in Pennsylvania, said Hillary Clinton had been badly damaged in the state by her promise to put coal miners out of work.

“I don’t know if he doesn’t remember, but there’s a county down here called Carbon County,” he said. “This guy wants to end the U.S. reliance on carbon-based fossil fuels? Well, he’s in for something.”

Trump won the state narrowly in 2016, the first time a Republican had triumphed there since George H.W. Bush in 1988. Pennsylvania and its 20 Electoral College votes will be another key battleground this time around.

Analysts say the Trump strategy is to return to the trade, energy, and immigration messages, which served him well four years ago, in an effort to improve turnout among an energetic base.

Democrats’ turn to the left on energy could help, according to Christopher Borick, director of the Muhlenberg College Institute of Public Opinion in Allentown. He said polls indicated that Pennsylvanians were opposed to a moratorium on fracking, although opposition is hardening toward the pipelines needed to move gas from the shale fields to refineries.

The sweet spot for voters, he said, was to propose tighter extraction taxes and regulation so that the state could benefit more from the energy boom. Calls to phase out or ban fracking risk handing the initiative to the Trump campaign.

“In a state that was so tight last time, where these small things matter, I think they would love to have Biden move left on environmental issues and maybe get a little bit ahead of the center in the state,” he said.

Patricia Kornick, spokeswoman for the PennEast Pipeline Company, said the plans had been through three years of scientific review by more than 23 regulatory agencies to minimize environmental impacts. Millions of customers would benefit, she said.

“Area families and businesses will receive reduced utility bills, and equally important, the increased stability — particularly during periods of peak demand — that comes from alleviating system constraints within the region,” she said.

Campaigners like the Christmans, whose family have farmed in Carbon County since the 19th century, see things differently. They say there is little public benefit in adding another pipeline to existing infrastructure and question why powers of eminent domain are being used to run it through the fields of corn that back onto their home.

“That’s the other issue — property,” said Christman, 71, as she pored over a map of 11 proposed pipelines put together by the group Save Carbon County.

“One of my neighbors said, 'You think you own your property until someone bigger and richer comes along.' People just feel helpless.”