A December RealClear-Emerson poll showed more Republicans than Democrats now support Fetterman. Among Democrats, Fetterman has a 31%-48% job approval rating. Among independents, he scores 30%-29%. And for Republicans, he’s at 57%-25%.

Will this lead to a primary challenge when Fetterman faces reelection in 2028?

“I don’t think it’s a possibility he will face a primary challenge — it’s a certainty,” said Democratic consultant T.J. Rooney. “Ironically, he will find himself in the very same position as the person who helped propel his career: former Pennsylvania Lt. Governor (now a California amateur stand-up comedian) Mike Stack. The parallels are stunning. Like Stack, Fetterman has become a bridge too far for virtually all Democrats.

“The only challenge for Democrats will be to not run too many candidates, so as to dilute the electorate and create a pathway for him, where none otherwise exists,” Rooney said.

Muhlenberg College Political Science Professor Christopher Borick agreed that Fetterman is likely to face a primary challenger.

“Real primary challenges to incumbent senators in Pennsylvania are rare but have happened,” Borick said. “Pat Toomey’s challenge of Arlen Specter in 2004 is illustrative. In that race Specter was vulnerable because many in the GOP base saw him as not conservative enough (aka a RINO), and Toomey was able to capitalize on this image in his bid to knock off Specter. While Specter narrowly survived the primary, the case demonstrates the conditions that can lead to a strong primary challenge.”

Borick added: “For Fetterman, there is a similar dynamic brewing. Many Democrats, especially progressives, have been less than thrilled with the choices Fetterman has made in Washington, both in votes and rhetoric.”

Borick noted that this has created an environment where Fetterman could face a formidable challenge from possible candidates like Conor Lamb, a former U.S. representative from Mount Lebanon whose star seemed to be rising before Fetterman came along and won the Democratic Senate primary in Pennsylvania. U.S. Rep. Chris Deluzio, who won the seat Lamb vacated to run for Senate, is also a potential challenger of Fetterman in 2028.

“If Fetterman were to receive a strong challenge and survive, it would likely leave him in a weakened position, given the large amount of resources necessary to withstand such a challenge,” Borick said. “Historically, incumbents that have received strong challenges perform worse in general elections than those that have run unopposed.”

Others believe even with competition in the primary, Fetterman would emerge as the likely winner in the general election.

“Fetterman is vulnerable in a Democratic primary because several of his recent high-profile votes don’t match his former progressive rhetoric and record,” said Jeff Jubelirer, a communications strategist with Bellevue Communications. “He campaigned as a left-of-center candidate — and formerly voted accordingly — but increasingly supports President Trump and the Republicans’ positions on key issues.

“Having said that, if Fetterman were to escape the primary with a victory, I’d expect him to be formidable and difficult to beat in the general election since he’d garner support from many Republicans who’ve been pleased with his turnabout,” Jubelirer added.

Charlie Gerow, a Republican strategist with Quantum Communications, believes Fetterman’s “independent streak” will draw a primary challenger from the left.  Gerow mentioned Lamb, who espoused centrist positions when he ran against Fetterman in 2022. But now Lamb has moved to the left to counter Fetterman’s shift to the center, Gerow said.

“Political chameleons are certainly not extinct,” Gerow said. “If or when Fetterman wins that primary, he will be in an even stronger position in the general election where many independent and some Republican voters see him as a voice of moderation and sanity in a swirl of ultra partisanship.”

Rooney added, “He’d do everyone a favor by running as a third-party candidate of some creation.”

That is also the path that Albert Eisenberg, principal of political messaging firm Red Bridge, recently suggested in Broad+Liberty, saying Fetterman should become an Independent and caucus with the Republicans. While Fetterman could still vote his conscience, “he will find on the Republican side a caucus that is actually interested in listening to him,” Eisenberg said.

Fetterman did not respond to requests for comment.