Former President Trump’s endorsement of Pennsylvania Republican Sean Parnell is elevating him as the early front-runner to win the state’s GOP Senate primary in one of the country’s most significant midterm contests.

The Wednesday endorsement of Parnell, an Army veteran who lost a high-profile House challenge last year, was a crucial step in boosting his name recognition and burnishing his bona fides with the GOP grassroots. But it also served to help kneecap his primary rivals, who saw their support for Trump as a key piece to their paths to the Republican nomination.

“Definitely, he's the odds-on favorite,” said GOP strategist Keith Naughton. “He was in the lead beforehand, but this really moves him ahead in the field.”

Parnell, who is ideologically aligned with Trump and close with his son, Donald Trump Jr., is running in a crowded primary for the chance to replace retiring Sen. Pat Toomey (R).

The Republican field, packed with backers of the former president, was flying under the radar amid the kickoff of a Democratic primary crowded with big-name lawmakers. But as the GOP contenders drew few headlines, many were touting ties to Trump or support for his agenda in an apparent attempt to win over his validation.

Trump’s endorsement Wednesday, in which he dubbed Parnell “a great candidate,” is likely sparking a scramble by the remaining candidates to retool their messaging surrounding their electability to a voter base that remains in lockstep with the former president.

“Now all of the sudden candidates instead of talking about why they're running, they have to start talking about why they're gonna hang around the race,” veteran Republican political consultant Christopher Nicholas said. “That can be debilitating.”

Among the other candidates in the race are Jeff Bartos, a businessman and GOP nominee for lieutenant governor in 2018; Carla Sands, a businesswoman and Trump’s ambassador to Denmark; and Kathy Barnette, a political commentator.

All three made their support for Trump clear, with Bartos’s campaign launch video saying Trump represented “someone listening to millions of Pennsylvanians,” while Sands’s video said her “leadership was recognized by President Trump.” Barnette’s campaign website prominently features the slogan “Pennsylvania First. American First.”

“There's no doubt that President Trump's supporters here in Pennsylvania are both vocal and active. And I anticipate them making up a majority of the folks who turn out in next year's primary,” said Allegheny County Republican Party Chairman Sam DeMarco.

But Trump’s endorsement is often considered a game-changer, leading some to speculate that the primary field will get culled.

“I think some of them are going to get out because of this,” Naughton said. “It's a crowded field, and it's going to be hard to completely clear the field, but I think a chunk of folks are going to get out.”

To be sure, the endorsement is not a silver bullet for Parnell.

Bartos has his own name recognition to run on from his campaign in 2018 and has centered much of his bid on his business efforts, while Sands is independently wealthy and can choose to self-fund her campaign.

Neither the Bartos nor Barnette campaigns responded to a request for comment from The Hill, but Sands insisted in a statement that Trump’s support for Parnell will not force her out of the race.

“Obviously we would have appreciated the President’s support, but I understand that his son has a long-standing personal relationship with Sean Parnell. I believe the President will be disappointed in this endorsement,” she said.

“There is no one in this race that can match my demonstrated commitment to the America First agenda,” she added. “We look forward to having the President on our team in the General Election.”

Still, Parnell and his allies have already indicated they plan to use Trump’s endorsement as a weapon in the primary.

“I think before the endorsement, Sean was the only candidate in the primary who had any traction whatsoever. And after the endorsement, I think this race is as good as over,” said a source close to the Parnell campaign. “Folks may be able to hoodwink Sands and Bartos into spending millions of their own dollars in this primary, but at the end of the day, it's not getting them anything. And if they want to light their money on fire, that's their right.”

Beyond narrowing his opponents’ lanes, Parnell is also expected to use Trump’s endorsement to expand his own.

Parnell is known mostly in western Pennsylvania, and raised about $560,000 in the second quarter, a figure that’s neither anemic nor eye-popping. An endorsement from Trump could both boost Parnell’s recognition in other parts of the state and beef up his campaign coffers.

“I wouldn't say he’s very, very well known, but he's pretty well known in western Pennsylvania because of the congressional race last year, and I think this just gives him a big boost statewide and gives him a profile and recognition that he didn't have before this endorsement,” said one Pennsylvania GOP strategist.

“It's not just Pennsylvania contributors that I think will start sending him some funds, I think it's national,” the source added. “I think it opens it up to the Trump network nationally, where prior to the endorsement, I think those who might have been interested in a Pennsylvania Senate race were kind of just waiting to see how it developed.”

Still, some Republicans suggest Parnell may face headwinds in a general election. Besides running with the support of a former president who lost Pennsylvania in 2020, Parnell is mostly known for losing to Rep. Conor Lamb (D) in a congressional district that is considered more conservative than the state at large.

Those questions take on heightened importance given the current makeup of the Senate, which, divided at 50-50, could change hands based on the results of any single contest.

“The trick for Parnell is, he's now running in a…state that's not as Trumpy as the congressional district in western PA that he ran for and lost last time,” said Nicholas. “The question remains, if Trump himself couldn't win here last time, how is someone trying to emulate Trump but who isn't Trump going to be able to win here in 2022?”

Other Republicans have pushed back on those concerns, with some noting that Parnell outperformed Trump in the district in 2020, suggesting Parnell’s appeal expands beyond just the Trump base.

“He's gonna have to appeal to a broader electorate than just the folks in the 17th Congressional District. But I believe that he understands that and is working on doing just that,” said DeMarco, whose county overlaps with Lamb’s district. “He overperformed the president's results, while his opponent underperformed Joe Biden's. So that's what I'm looking at to indicate why I think he'd be electable.”

And on top of that, Republicans say the midterm environment will be different than the 2020 race and that 2022 will be dominated by issues like the evacuation in Afghanistan — which, given Parnell’s extensive service there, plays right into his hands.

“Sean has been everywhere, he's been all over Fox, all over conservative media, doing tons of local media, doing events in Pennsylvania. And look, politics is about timing. And is there a candidate with a better background running for office today than Sean Parnell, a bona fide war hero who spent more time in combat in Afghanistan than any other person?” the source close to Parnell’s campaign said.

Beyond supporting Parnell, the boost could also pay dividends for Trump. The former president relies on his endorsees’ success to maintain his own high standing among Republicans, and after a loss by one of his chosen candidates in a Texas House race, which was followed by a victory in an Ohio primary, he could be seeking to get back on a winning streak.

“Trump needs to start picking winners, and I think he saw Parnell as a good candidate,” Naughton said. “This is a bandwagon endorsement by Trump to try to pick a winner and try to restore a little bit of that luster.”