Added up district by district, the phenomenon is creating a vastly different Republican Party than the one that nominated Trump in 2016, four years after elevating Mitt Romney to the presidential race — as evidenced by the fact that “Romney Republican” has become an epithet across numerous 2020 Republican primaries.

The House GOP Conference is set to be smaller but Trumpier next year, tightening the president’s hold on the top ranks of the party. And while some Republicans worry this will make it tougher to win back the House, the growing Trump footprint in safe seats means that the next time they do win the majority, the president’s political style and staunchest backers will play a big role in the national government whether or not Trump is still on the scene.

The latest party cleansing played out on Tuesday in Florida, where voters replaced retiring GOP Rep. Francis Rooney — a prominent Trump critic who considered voting for impeachment — with Byron Donalds, one of several devotees who competed to represent the heavily Republican district by showing how strongly they’ve stood with Trump.

"I spoke at both of the president's rallies during the November election in 2016 here in southwest Florida," Donalds, a state representative who could be the only Black Republican in the House next year, said in a pre-primary interview. "I gave the president an award in 2019. I was at the launch of Black Voices for Trump. I think that if anybody in this race has shown that they're a supporter of the president — before they actually decided to run for office — it's me."

Adherence to Trump has quickly surpassed taxes and spending as the most dominant issue to Republican primary voters, said David McIntosh, the president of the anti-tax group Club for Growth. A candidate can jump up somewhere between 15 to 20 points in the group’s internal polling when voters learn of a Trump Twitter endorsement, he said. And the Club has found a potent campaign attack in revealing that a candidate gave to Romney in 2012, but not Trump in 2016.

“That tells the voter: OK, maybe in his heart he says he’s a Trump Republican, but maybe he’s really a Romney Republican,” McIntosh said. “In Republican primaries, if they feel that somebody will not be loyal to President Trump, their poll numbers go way down.”

Trump’s name or likeness appeared in over 60 percent of the over 600 broadcast TV ads aired in Republican primaries this cycle, according to a POLITICO analysis of data from the media tracking firm Advertising Analytics, with candidates regularly echoing Trump’s vows to “build the wall,” eschew political correctness and restore American greatness.

But as the primary season comes to a close next month, there is a growing concern among some in the GOP that their conference will be dominated by people whose guiding force is not principle or ideology but a blind devotion.

“That’s a real risk for Republicans,” said former Rep. Charlie Dent (R-Pa.), who retired in 2018. “That they’re going to get some guy wearing a MAGA hat as opposed to people who might have a greater sense of what they believe in other than the president.”

Nearly 47 percent of the 241 Republicans in the House when Trump took office have or will have left the Chamber by 2021 — and that percentage could grow if more GOP incumbents lose in November. While some departed to join Trump's administration or seek a higher office, roughly 90 have either retired or lost reelection.

This reformation of the House GOP Conference is compounded by the fact that many of the retirees are among the few lawmakers willing to offer at least a modicum of opposition to Trump, on issues of principle or policy.

Rep. Mac Thornberry (R-Texas), who frequently critiques Trump on foreign policy, will be replaced in Congress by Ronny Jackson, the former White House doctor who suggested that with a better diet Trump might have been able to live to the age of 200. Rep. Paul Mitchell, (R-Mich.) — who admitted he is retiring after just two terms in part out of frustration over the president's tweets — will be succeeded by Lisa McClain, a businesswoman who sparked controversy by attempting to hold a Trump rally at a local cider mill during the pandemic. (Trump’s former campaign manager Corey Lewandowski was set to attend.)

Rep. Phil Roe (R-Tenn.), who said he would write in another Republican on his 2016 ballot out of disgust over Trump’s comments toward women, will turn his seat over to Diana Harshbarger, who pitched herself as a “Trump conservative” as she featured the president in several TV ads. And Rep. Martha Roby (R-Ala.), who once publicly declared that she could not vote for Trump and look her children in the eye, will be followed in Congress by former state Rep. Barry Moore, who says he was the first elected official in the country to endorse Trump for president.

Moore, who unsuccessfully challenged Roby in 2018 following the congresswoman’s anti-Trump apostasy, trailed the first-place finisher by 18 points in the first round of the primary. He prevailed in a primary runoff after leaning heavily on his early allegiance to Trump, with footage from the August 2015 rally where he endorsed the president appearing in his campaign ads.

"Having the videos and the footage and being at the convention in Cleveland, it just added credibility to the fact that when we said we supported the president, we actually did," Moore said in an interview. “A picture is worth 1,000 words and I had a boatload of pictures with him. My opponent didn’t have anything.”

The GOP base’s full embrace of Trump could complicate any post-mortem efforts by the party should Democrats capture the White House in November.

House Republicans leaders and the National Republican Congressional Committee have already faced blowback for their plans to welcome Georgia’s Greene into their caucus. In addition to her promulgation of QAnon theories, she has also taped hours of videos making racist comments.

But some operatives have warned if the Republican Party is dominated by loud voices pandering to the extremes, it could undermine the GOP's ability to rebuild a majority-winning coalition.

“What the House Republican Conference and the NRCC are going to have to decide going forward is whether they’re content to remain in the minority with that kind of member making up the House Republican Conference or whether they want to do the work of expanding the tent,” said Michael Steel, a former top aide to ex-Speaker John Boehner.

“The party needs to be defined by its best arguments, not the worst of its excesses,” he added.

Should Trump win reelection, he will find himself with an iron grip on a Republican conference pruned of many who would speak out against him. In interviews, few Republican primary candidates are willing to identify areas where they would break with Trump's policies.

Rooney, who announced his retirement just days after musing on TV that he would consider impeaching the president, correctly predicted in an interview late last year that the race to replace him would follow that trajectory.

“A large segment of our district is very, very significantly loyal to President Trump. They’re going to want to see a candidate that they have absolute confidence in, that is not going to deviate from what the president wants to do," Rooney said. “That has put me at odds with some of them at times because I am my own person."