Conor Lamb, the apparent winner of this month’s special congressional election in Pennsylvania, is filing petitions to run in a new, less conservative district in the Pittsburgh suburbs — but the Democrats already running in that race aren’t all clearing his path ahead of the May 15 primary.

“Everybody is welcome to run in this election,” said Lamb’s campaign manager, Abby Murphy, who added that 4,000 signatures had been gathered in four days, with only 1,000 needed to make the ballot. “But there’s one incumbent congressman, and that’s Conor Lamb. The congressman-elect is focused on getting to work for the people of the [old] 18th District while getting caught up on the issues affecting these new voters in the 17th.”

Lamb is one of three Democrats expected to run for the new 17th Congressional District, which includes his home precinct, the parts of Allegheny County where he ran strongest last week, and Republican-leaning Beaver County. In the 2016 election, Donald Trump and Hillary Clinton ran even in the new district; Rep. Keith Rothfus (R-Pa.), a conservative who found his home drawn from a safe seat to the new swing seat, has become viewed as one of the party’s most vulnerable incumbents. The entire map had been altered by a state Supreme Court ruling against Republican-drawn districts; the old 18th district will cease to exist at the end of this year.

Once-safe Republican districts suddenly in play as Democrats expand the map

Before Lamb’s apparent victory — Republicans have not conceded and the Associated Press has not called the race — the primary in the 17th District had pitted lawyer Beth Tarasi against biologist John Stolz, teacher Aaron Anthony, energy executive Ray Linsenmayer and psychologist Erin McClelland.

National Democrats had not intervened to clear the field, though Anthony quit the race Monday night, and Stoltz and McClelland did not file on Tuesday. McClelland, who challenged Rothfus in his old district, lost by 24 points in 2016. Tarasi had raised more money than the rest of the field combined, and built a network of supporters. At a local party meeting last week, she gathered signatures in person, telling Democrats about her story as an athlete who took advantage of Title IX and became an attorney, while raising two children by herself.

“I have a path to victory,” Tarasi said in an interview last week. “I feel really strongly that women are underrepresented in this district, and it’s time we change that.”

Tarasi, like the rest of Lamb’s likely challengers, argued that the politics that let him pull an upset in a conservative district are out of step with the more moderate 17th.

“I think health care should be affordable or accessible to everybody, and I think assault weapons should be banned,” said Linsenmayer in an interview. “Conor Lamb frankly took the opposite position when he was running in the more rural areas of the 18th District.”

Lamb, who has spent the days since the election talking to voters in the new district — including at a St. Patrick’s Day parade — is not blowing off the challenges. “The congressman-elect is happy to debate and meet and talk to as many people as possible, just as he did in the 18th District,” Murphy said.

The scrambled electoral map has created a similar situation for Rick Saccone, the Republican state lawmaker whom Lamb appeared to defeat last week. The day after the election, Saccone filed to run in the new 14th District, a stretch of southwest Pennsylvania that includes the counties where he ran the strongest but not his home. (That is in the now-strongly Democratic 18th District.) He’s facing a primary of his own — a rematch against fellow state lawmaker Guy Reschenthaler, whom he had defeated in the local party convention to pick a nominee in the special election.

There’s less ideological separation between Saccone and Reschenthaler than between Lamb and his new Democratic opponents. But Tarasi, Lamb and Linsenmayer agree on one issue: They’re not comfortable with Nancy Pelosi as the Democrats’ leader in the House.

“She’s done a wonderful job, but I think it’s her time,” Tarasi said.