HAMMONTON, N.J. — There’s a fire in the Pine Barrens, and it’s creeping toward Rep. Jeff Van Drew.

The New Jersey congressman is one of just two Democrats nationwide who voted Thursday against an impeachment inquiry of President Donald Trump, and progressives in his district have flocked to Facebook and Twitter to express their anger.

“This guy is part of Team Trump,” said one poster in a Facebook group for progressive Democrats in Van Drew’s district.

“Did somebody say ‘primary challenge'?” another poster wrote. “Trust me, Jeff, there will be one.”

Political experts say Van Drew’s “nay” vote is shrewd and not unexpected.

Like all House members, he’s up for reelection next year. Van Drew, a 66-year-old former dentist, won the seat in 2018 after more than 15 years in the state Legislature.

And though New Jersey traditionally runs blue, his district — which stretches from the Philadelphia suburbs in Gloucester County south to Cape May and north of Atlantic City into Burlington County — flips. Slightly more than 50% of the district voted for Trump in 2016, a five-point margin over Hillary Clinton. Fifty-three percent voted for Barack Obama both times he ran. Neither Democrats nor Republicans can claim more than a third of its registered voters, according to the most recent data.

For Van Drew, this vote didn’t come easy. “I thought really long and hard on it,” he told reporters Thursday. “You can never make everybody happy; that’s the tough part about this.”

Many progressives aren’t sympathetic. “It was the last straw,” said Melissa Tomlinson, a member of NJ 21 United, a progressive group in South Jersey. “He doesn’t represent me.”

Others feel the vote shows Van Drew’s true colors. “He’s a Democrat in name only,” Helen Duda, founder of NJ CD-2 Progressive Democrats, said during an interview Friday, over lunch in the Harley Dawn diner in Hammonton.

Since the vote, she said, more than 100 people reached out to her and other activists, looking for a way to channel their frustration with Van Drew into action. She talked with them in diners, and traded posts with them on Facebook and Twitter, delivering the same message: “Elect true Democrats."

But activists like Duda are facing an uphill battle, according to political analysts.

“South Jersey is a lot less supportive of the impeachment inquiry,” said John Froonjian, executive director of Stockton University’s William J. Hughes Center for Public Policy.

Forty-seven percent of residents in the eight South Jersey counties — nearly half that make up Van Drew’s district — were opposed to the impeachment inquiry, while 46% were in favor, according to a Stockton University poll last month. Fifty-six percent of North Jersey residents favored an inquiry, the poll found.

For many progressive activists in Van Drew’s district, the road to ousting him in 2020 starts Tuesday, when New Jersey votes to elect members to its General Assembly. Three moderate incumbents — one state senator (the only state Senate seat at stake this year) and two Assembly members — are seeking reelection and bill themselves as the “Van Drew Team.”

Activists have fielded three write-in candidates to challenge them.

“They need a jolt,” said Duda. “We don’t have to settle for the status quo.”

But for the write-in candidates and progressive organizers, their goal isn’t actually a win Tuesday.

“It’s about Van Drew,” Julia Hankerson, one of the write-in candidates for the Assembly, said Friday during an interview in Cape May Court House.

The three challengers see their write-in candidacies as a way to mobilize progressives in the district, and generate energy they can harness as the 2020 Democratic primary election nears, Hankerson said.

Political experts are skeptical.

“There isn’t a single person there who has the profile and can galvanize enough support,” said Patrick Murray, director of Monmouth University’s polling institute. “They need an Alexandria Ocasio-Cortez-level candidate,” he said, referring to the high-profile liberal Democratic congresswoman from New York City.

“Jeff Van Drew is a very successful politician because he is in tune with [his] district,” said Benjamin Dworkin, director of Rowan University’s Institute of Public Policy. Progressive Democrats, he predicted, “don’t have enough votes.”

In his 2018 primary, Van Drew handily beat a progressive candidate, Tanzie Youngblood, winning 57% to 19%. He topped Republican Seth Grossman in the general election by an eight-point margin.

Van Drew also has not ruled out a vote to impeach Trump, which could complicate matters for progressives who are galvanizing against him primarily because of his stance on the impeachment inquiry, said Murray.

“I hope I’m a reasonably intelligent person, and I’m always a very open person to all ideas," Van Drew told reporters after the vote. "So if something comes along that is really treasonous or truly a high crime and truly is at the level of impeachment — please understand how important and how serious impeachment is — at that time, of course I would.”

And about the progressives eager to challenge him? He’s not worried.

“If I’m primaried, I’m primaried,” Van Drew said. “That’s the American way.”

Activists like Duda are ready for the challenge: "We’re coming for him.”