Hard-right Republicans in Congress have so far failed to oust the handful of their GOP colleagues they’ve targeted in primaries this year. But the effort is moving forward, and Rep. William Timmons of South Carolina is their next target.

It’s the latest incumbent primary in an ongoing proxy war for House GOP divisions over whether it’s best to work across the aisle and find some amount of common ground to pass legislation — or hold the conservative line at all costs, even if it means grinding Congress to a halt.

GOP Rep. Nancy Mace’s challenge in her primary has attracted more attention. But Timmons, a three-term congressman, is also facing a competitive primary Tuesday against state Rep. Adam Morgan, the leader of the Freedom Caucus in the South Carolina legislature, who has support from several members of the congressional caucus in Congress.

For Timmons, this race is not about his conservative credentials.

“This isn’t a ‘Freedom Caucus versus William Timmons.’ This is a fringe, loud component of the Freedom Caucus,” Timmons said. “I have a more conservative voting record than six out of the nine people that have endorsed my primary opponent out of the Republican conference.”

“So it’s not about policy,” Timmons said. “It’s about tactics.”

Timmons does have some major advantages, including spending and support from outside groups and the most coveted endorsement in GOP politics: former President Donald Trump.

Yet he still could be vulnerable. Timmons narrowly avoided a runoff two years ago against lesser-funded opponents and then faced allegations of an extramarital affair. Timmons declined to comment on those allegations, but he has since divorced and told NBC News that he and his ex-wife are “still on very good terms.” South Carolina Republican strategists say the allegations could still be a problem for Timmons in the socially conservative district.

Proxy fight

GOP lawmakers on both sides of their internal fight over tactics have grown more willing to publicly back primary challengers against their own colleagues, including in Timmon’s primary.

Morgan has endorsements from Rep. Matt Gaetz of Florida and members of the House Freedom Caucus, including Chairman Bob Good, R-Va., and Rep. Ralph Norman, Timmons’ South Carolina colleague. Timmons also boasts support from several Freedom Caucus members, including Rep. Byron Donalds of Florida and Rep. Jim Jordan of Ohio, one of the founding members, as well as GOP Gov. Henry McMaster.

Gaetz campaigned with Morgan in April after sharing a video of him railing against special interests on the state House floor, helping to draw attention and money to Morgan’s campaign.

“I need backup like him in Congress in order to save this country and defeat the establishment,” Gaetz said in a statement.

Gaetz, Good and some Freedom Caucus members have also backed primary challengers against Reps. Mike Bost of Illinois, Tony Gonzales of Texas and Don Bacon of Nebraska. Those incumbents prevailed, but Morgan thinks this race will be different.

“If you see the energy on the ground, people are ready for a change,” Morgan said in an interview. “And I think that it would probably be a very different race than some of the others. In our area, we have a very informed voter base that have already soured to our incumbent and they’re really ready for a strong alternative.”

Morgan said Timmons’ House speaker vote for Kevin McCarthy last year was “definitely a factor” in his decision to run, and he supported Freedom Caucus members’ push for House rules changes that weakened the central control of the speakership.

Morgan said some Freedom Caucus members told him Timmons pressured them to support McCarthy, suggesting they could lose committee assignments if they did not fall in line.

“Not only was my member missing in action, as is his usual M.O., but he was actually working for McCarthy, against conservatives,” Morgan said.

Timmons, a former member of the panel that doles out committee assignments, said it is “not true” that he threatened any lawmakers on behalf of leadership. He said he told some lawmakers that “merit, seniority, and team player” mentality are factored into committee posts.

Morgan has sought to cast Timmons as “do-nothing moderate” who has not supported conservative policies like cutting government spending, opposing diversity initiatives, and opposing aid to Ukraine. (Timmons counters that did vote against the most recent Ukraine aid package.)

Timmons, meanwhile, has cast Morgan as too extreme and uncompromising. His closing attack has centered on Morgan’s support for an amendment that said a “pregnant woman who intentionally commits an abortion” could be penalized with up to two years in prison or fined up to $5,000. Timmons argued such positions are counterproductive for the anti-abortion rights movement and could ultimately help Democrats win in November.

”Protecting life is not a liability for Republicans,” Morgan countered. He dismissed the attack and argued that he has voted in other instances to exempt women from criminal prosecutions.

Morgan said the amendment was aimed at solving a “loophole” relating to “when women who perform abortions on themselves,” appearing to refer to women who have medication abortions, which account for the majority of abortions in South Carolina.

Morgan said he supported the amendment “because we want to actually protect lives.”

Trump factor

Tuesday’s race in the 4th District will also test the power of Trump’s endorsement in a competitive primary.

Trump carried the upstate district, which is home to scores of evangelical voters, by a whopping 32 points in 2020, the widest margin of South Carolina’s seven districts, per calculations from Daily Kos Elections. In this year’s presidential primary, Trump won the 4th District by 20 points, with 60% of the vote.

“There’s no question it helps [Timmons] in a Republican primary,” said South Carolian GOP strategist Chip Felkel, who is not involved in the race, adding that it likely boosts Timmons in more rural parts of the district outside Greenville and Spartanburg.

Timmons launched a TV ad with Trump speaking directly to camera and calling Timmons “an America first patriot.”

“A lot of people want to support Trump,” Timmons said. “And if Trump says, ‘This is my guy, I need him to help me get our country back on track,’ that’s what they’re gonna do … He is supporting me because of my results and because we’re like-minded.”

The ad underscores Timmons’ sizable financial advantage in the race. His and allied outside groups, including one tied to the cryptocurrency industry, have spent $3.1 million on ads to Morgan’s $221,000, according to the ad-tracking firm AdImpact.

But Morgan isn’t concerned that Trump’s endorsement will hurt his campaign.

“People in this district love the president, support the president, but they’re not just going to vote for their representative because somebody tells them to,” Morgan said. “They’re going to do the research themselves.”

It’s not unheard of for a Trump-backed incumbent to lose a primary to the likes of hardline Republicans like Good and Rep. Lauren Boebert, who beat a sitting member in Colorado in 2020. But it is rare.

“Thus far it’s been swinging a miss in some states,” South Carolian GOP strategist Dave Wilson said of the hardliners’ primary efforts.

“There’s a possibility they actually may get a hit with Adam Morgan,” Wilson added. “But the curveball of Donald Trump, so to speak, may be enough to strike them out here as well.”

This article was originally published on NBCNews.com