Former President Trump’s war with his staunch GOP critics on Capitol Hill is seeping into every corner of the 2022 campaign trail.

Texas GOP congressional candidate Morgan Luttrell recently called Trump foe Rep. Adam Kinzinger (R-Ill.), asking the fellow military veteran to donate to his primary campaign, a GOP source said; Kinzinger did so, sending Luttrell a donation from his anti-Trump Country First political action committee.

But Luttrell, a retired Navy SEAL and the favorite to succeed retiring Rep. Kevin Brady (R-Texas), faced so much backlash from Trump loyalists, he was forced to quickly send back the donation to Kinzinger, GOP lawmakers familiar with the situation told The Hill on Tuesday.

The strange episode highlights just how cautious inexperienced Republican congressional candidates need to be as they navigate a perilous campaign cycle where Trump — the de facto leader of the GOP and its possible nominee in 2024 — is vowing to destroy any fellow Republican who opposes him or anyone who aligns with their cause.

“Rule one on a campaign is ‘do no harm,’ and I wouldn’t have allowed for that contribution to be accepted,” said one GOP campaign strategist who works with House candidates.

The situation also shows just how challenging it will be for Kinzinger — who has raised more than $2 million this year — to play in contested GOP primaries around the country. While GOP candidates are eager to receive donations, they may not want to accept money from Kinzinger if it results in vicious attacks from Trump and his loyalists.

Kinzinger said in October that this term, his sixth, will be his last in Congress after Illinois Democrats approved a new congressional map that put him in a liberal district. But the Iraq and Afghanistan war veteran said in his retirement video that he will be focusing on the “broader fight nationwide” against Trumpism.

“My suspicion is that Adam Kinzinger will become a lot more deft at concealing the way he’s deploying lobbyist and special interest money to try to remake the Republican Party in their image — not President Trump’s,” Rep. Matt Gaetz (R-Fla.), a top Trump ally, told The Hill on Tuesday.

“I wouldn’t want to run as a candidate in a Republican primary, taking money from Adam Kinzinger’s PAC, but I don’t suspect that he’ll be offering,” Gaetz said.

Kinzinger, 43, is one of 10 House Republicans who voted to impeach Trump for his role in the Capitol attack. He also serves on the special committee probing the Jan. 6 attack by a mob of Trump supporters. He declined to comment about the Luttrell donation. A spokesperson said Kinzinger only gives to “serious legislators” who demonstrate leadership.

The Luttrell campaign did not respond to a request for comment.

Luttrell’s twin brother, Marcus Luttrell, is a close ally to former Texas Gov. Rick Perry (R) and a retired Navy SEAL. He was depicted in the 2013 Mark Wahlberg film “Lone Survivor” about a failed counterinsurgent mission against the Taliban.

Kinzinger first met the Luttrell brothers in 2019 on the Luttrell ranch in Texas during the taping of a Fox News special called “Modern Warriors.”

The trio have been friendly ever since.

Minority Leader Kevin McCarthy (R-Calif.), who has his eye on the Speakership, also has been friendly with Morgan Luttrell. While Luttrell, so far, is not one of McCarthy’s eight “Young Guns” for 2022, the GOP leader did invite and host the former Navy SEAL at the “Gold Caucus Summit,” McCarthy’s summer donor retreat in Jackson Hole, Wyo., a spokesman said.

“Leadership is high on him,” one House Republican lawmaker said of Luttrell. “Trump World is upset that [leadership] is pumping him up since he’s cozy with Kinzinger.”

Proxy battles are also being waged between the pro-Kinzinger and pro-Trump camps in other parts of the GOP conference. This week, a video emerged on social media showing Rep. Dan Crenshaw (R-Texas), also a former Navy SEAL and decorated war vet, at an event with Luttrell and Texas GOP candidate Wesley Hunt, defending Kinzinger and taking aim at the Trump-aligned House Freedom Caucus.

“Why am I supporting these two? … There’s two types of members in Congress: There’s performance artists and there’s legislators. Now, the performance artists are the ones who get all the attention … They are the ones you think are more conservative because they know how to say slogans real well,” Crenshaw, who lost his eye in a roadside bomb attack in Afghanistan, told the crowd.

He explained that during the first two years of Trump’s presidency, when the GOP controlled all of government, there were Republicans who voted with Trump’s agenda and those who often broke with Trump.

“No. 2, this is probably going to make you cringe a little bit, is Adam Kinzinger. Voted with Trump almost 99 percent,” Crenshaw said. “You know who was at the bottom? Everyone in the Freedom Caucus, all of them.

“We have grifters in our midst … I mean in the conservative movement. Lie after lie after lie.”

Crenshaw’s remarks infuriated some Freedom Caucus leaders, who lashed out at him and his defense hawk allies on Twitter. 

“Who told you this was a good idea @DanCrenshawTX? Neo-Conservative is just another way of saying ‘not conservative,’ ” Rep. Warren Davidson (R-Ohio) said in response to the video clip. “Every actual conservative scorecard exposes these lies. Actual conservatives oppose bankrupting America, spying on Americans, and crony surveillance capitalism.”