When Doug Mastriano bested Pennsylvania's GOP establishment to win the nomination for governor, top Republicans feared he was too extreme to win independent and mainstream party support in the general election.
Now those predictions are starting to look prescient.
On Wednesday, nine former and current Republican officials publicly endorsed Mastriano's Democratic opponent, state Attorney General Josh Shapiro.
Other Republicans told NBC News they'll just abstain from voting in the governor's race - warning signs for Mastriano that he's struggling to broaden his support in one of the country's tightest swing states.
Mastriano, a state senator, has been slow to reach out for the support of his former primary rivals. He refuses to talk to most of the local or national media, limiting himself to conservative media outlets, where he talks about abortion restrictions and unfounded election fraud claims.
"Most Republicans recognize this is an uphill slog," said Phil English, a Republican former member of Congress who hasn't publicly endorsed a candidate in the governor's race. "Republicans are looking to Mastriano to appeal outside his base and show an awareness of what a Republican candidate for governor needs to win. But he doesn't enjoy any of the traditional base-broadening qualities for successful statewide campaigns."
Mastriano's first high-profile hire after the May 17 primary was indicative of his campaign's direction: Jenna Ellis, the former Donald Trump lawyer who, along with Mastriano, tried to help overturn the 2020 presidential election results. Both Ellis and Mastriano were subpoenaed by the House committee investigating the Jan. 6 riot. Ellis was subsequently subpoenaed by a Georgia prosecutor investigating Trump's election meddling in the state.
Mastriano is also trailing Shapiro when it comes to getting his message out through campaign ads. Shapiro has spent more than $4.7 million on ads since the primary, compared to no spending by Mastriano, according to the media tracking firm AdImpact.
The Republican Governors Association, which has spent millions on GOP candidates this year, has no plans to help Mastriano right now.
One of the Republicans who ran against Mastriano in the primary, conservative activist and consultant Charlie Gerow, said that he recently spoke to Mastriano, who he said is aware that his campaign needs to attract more than the Trump base that propelled him into office as a state senator.
"Mastriano would say he needs to expand his appeal. It's one of the things we talked about," said Gerow, who said he pledged his support to Mastriano. "He's neck and neck with Shapiro, and any Republican in that position in this state is in good shape. ... Mastriano has not yet hit his stride."
Other GOP opponents from the primary have yet to publicly endorse Mastriano. Many didn't reply to calls seeking comment. During the primary, Republican establishment figures feared that nominating Mastriano would be such a drag on the party in November that they tried to clear the multicandidate field to make it easier to beat him. But Mastriano won with 44 percent of the vote, a result that was boosted by a late Trump endorsement once it became clear he was in a strong position to become the nominee.
Mastriano's primary win on a shoestring budget showed he had an ability to inspire die-hard grassroots GOP support, which he's counting on for the general election.
Considering the national headwinds facing Democrats - high inflation and gas prices under an unpopular Democratic president - Republicans were hoping to be in better shape in Pennsylvania. Instead, they're faced with internal doubts about Mastriano's viability in November and a Senate nominee, Mehmet Oz, who is trailing his Democratic opponent, Lt. Gov. John Fetterman, in a recent AARP poll by a wider margin than Mastriano trails Shapiro.
"Both these races should be slam dunks given the climate, but thanks to Donald Trump and some idiots in our party, we have set up the possibility of losing them both," said Jeff Piccola, a former state representative who resigned as the York County Republican Party chairman partly because of Mastriano's ascent.
"Unless something dramatic happens, I can't cast a vote for him," said Piccola, who hasn't endorsed Shapiro.
One of the Republicans who announced backing for Shapiro on Wednesday, Lawrence County Commission Chairman Morgan Boyd, said Mastriano was too far outside the mainstream to earn his support.
"I wouldn't define Mastriano as a Republican but as a populist," Boyd said in an interview. "His claims about the election turn me off. His divisiveness turns me off."
The list of GOP officials endorsing Shapiro includes two former U.S. representatives, Charlie Dent and Jim Greenwood; former state Supreme Court Justice Sandra Schultz Newman; former state House Speaker Denny O'Brien; former state Reps. Dave Steil and Lita Cohen; former Lt. Gov. Robert Jubelirer; and former Montgomery County GOP Chair Ken Davis.
Huntingdon County GOP Chair Arnie McClure, who's backing Mastriano, called the Shapiro backers "Republicans in name only" and compared them to those Republicans who "sabotaged" the last right-wing nominee for governor, Scott Wagner, who lost by 17 percentage points in his bid to unseat Gov. Tom Wolf.
Former GOP Chair Rob Gleason, who is supporting Mastriano, wasn't impressed with Wednesday's list, calling the endorsers of Shapiro "over-the-hill Republicans that have no influence and no one cares what they think."
But Sam Chen, an assistant political science professor at Northampton Community College who has consulted for Republican candidates, said that Pennsylvania is known for split-ticket voting and that the GOP doubts over Mastriano are real.
"It's widespread, but it's not as vocal as it was during the primary. Now they're muted because there are still so many party-or-bust people," Chen said. "In private conversations, there's still lots of heartburn Mastriano can't win. I don't think it's impossible. But it's tough."