Fred Upton first got elected to Congress in 1986 at the tender age of 33 and never lost a race after that. Only once did he win by less than double digits.

He’s not even 70 and his party is poised to win big in the midterms. As a senior member of the caucus, he’s in line for plum committee assignments, including chairmanships. (He chaired the powerful Energy and Commerce Committee for six years while Obama was president.) Because he’s a centrist Republican who’s well-liked by both sides, he’d also make a fine Republican Senate prospect in Michigan, where the GOP has had trouble winning statewide lately. A very rich man, Upton could even self-fund.

But his career is over for the same reason Anthony Gonzalez’s, Adam Kinzinger’s, and John Katko’s careers are over. He insisted on holding Trump accountable for inciting an insurrection against the government, an unforgivable affront in a party that’s degenerated into an authoritarian cult of personality. So he’s done.

.@RepFredUpton announces retirement: "Even the best stories has a last chapter. This is it for me." pic.twitter.com/32Sj1tqKJj

— CSPAN (@cspan) April 5, 2022

He was running campaign ads as of late February. As recently as two days ago, he talked tough about the significance of his upcoming primary. That contest, in Michigan’s newly redrawn Fourth District, pitted Upton against fellow GOP incumbent Bill Huizenga — who’s been endorsed by Trump, of course, as part of his revenge campaign against pro-impeachment Republicans like Upton. What would it mean for you to defeat Huizenga in that primary, NBC asked him? Upton was clear:

WATCH: Rep. Upton (R-Mich.) talks about fmr. Pres. Trump’s support for a primary challenger.@vaughnhillyard: “If you win your race against this Trump-backed challenger, what message is sent?”@RepFredUpton: “That [Trump]’s not as strong as he might have thought he was.” pic.twitter.com/qNYeipZ0rP

— Meet the Press (@MeetThePress) April 4, 2022

Having framed the race as a sort of referendum on Trump, he’s now decided to bow out two days later. Which means, I guess, that he believes … Trump *is* as strong as he thought he was?

What changed his mind? Did he get a bad poll?

Upton insisted today that his polls against Huizenga looked good. But is that true?

Upton has been viewed as having a fundraising and geographic advantage in the new district, keeping more of his current territory than Huizenga did after redistricting.

But some analysts had said the pro-Trump Huizenga would have an edge in a head-to-head race, noting the new district covers counties where grassroots supporters of Trump last year censured Upton over his vote for Trump’s impeachment.

Upton stood to potentially gain from a third contender in the GOP primary, state Rep. Steve Carra of Three Rivers, because it was thought Carra would split the pro-Trump vote with Huizenga. But Carra dropped out March 15 and endorsed Huizenga after the Trump endorsement.

Maybe Upton believed he could get past Huizenga, however narrowly, but was then likely to be upset in the general election as spiteful Trumpers opted to stay home instead of turn out. He might have been willing to undertake one tough campaign but not two. And since there’s no evidence of Trump intending to step away from politics — on the contrary — his reward for succeeding this year would be another Trump-backed primary challenger in 2024.

Even if he believed he could survive all that, he might reasonably look with disgust at the prospect of a Kevin-McCarthy-led House majority in which the leadership lives in fear of crossing loudmouthed cranks like Marjorie Taylor Greene. “Fred Upton is one of the members there to work hard and do the right thing. A workhorse, not a show horse,” Doug Heye tweeted this morning. Upton’s a policy guy, and the GOP no longer concerns itself much with serious policy. Maybe the time suddenly seemed ripe for a change of career. Let the Madison Cawthorns in the caucus have the run of the place. It’s what the Republican base wants.

Trump boasted recently that six of the 10 House GOPers who voted to impeach him are either gone or likely gone. That’s plausible.

More Trump in Mar-A-Lago on the House Rs that voted for his impeachment after Jan. 6: “I was just telling John, the good news is 6 out of the 10 are gone or effectively gone.”

Calls #SC07 Rep. Tom Rice an “idiot” who “voted in the spur of the moment. Everybody was surprised.” pic.twitter.com/bDTOtgZmll

— aaron navarro (@aaronlarnavarro) March 31, 2022

In addition to the four retirees (Gonzalez, Kinzinger, Katko, and now Upton), Tom Rice is trailing in his primary in South Carolina. And then there’s Liz Cheney, who needs a miracle to survive her statewide primary in blood-red Wyoming. Team Cheney is quietly hoping for a big showing from anti-Trump Democrats in her favor but the math isn’t there for her, writes Geoffrey Skelley. To win in a state like Wyoming, you need Republican votes. Lots of them.

So let’s do a little back-of-the-envelope math to consider Cheney’s position based on what we know about the current state of the race and recent Wyoming primaries. There has been little recent public polling of the race, but a December survey from SoCo Strategies put her behind Hageman by 20 percentage points, and older polls found her support or favorability among Wyoming Republicans in the 20s — evidence that she’s in rough shape. For argument’s sake, let’s say that Cheney trails by 10 points among registered Republicans in the final days of the primary campaign (possibly a rosy scenario, considering her polling numbers). So Hageman has 50 percent, Cheney 40 percent and the four or so other candidates attract the remaining 10 percent (the candidate filing deadline is May 27, so the field could expand or retract further). If there are around 110,000 voters who were registered Republicans before primary day — a reasonable guess since nearly 117,000 total voters participated in the 2018 GOP primary for governor — Hageman would lead by around 11,000 votes. Based on the 2018 primary, Cheney would then need nearly 60 percent of the total Democratic primary voters to not only switch to vote in the GOP contest but to also vote for her.

I’m quite skeptical that Cheney’s going to pull 40 percent of the Republican vote against Hageman. And equally skeptical that more than half of the Democratic primary electorate is preparing to switch parties on primary day to vote for Dick Cheney’s daughter.

So, yeah, at least six out of 10 of the pro-impeachment Republicans are likely goners.

Trump had better hope so, at least, since how his candidates fare in the primaries will be widely read as a measure of his influence over the party. If he nukes his enemies, he’s the prohibitive favorite in 2024. If he sees his candidates lose, Ron DeSantis will take note. Exit quotation from GOP pollster Glen Bolger, noting David Perdue’s struggles in Georgia: “I don’t know whether he is letting emotion rule his decision making or if he is getting bad advice, but it seems like he is picking candidates who are pretty weak, and that’s not a place — when you’re trying to be kingpin — where you want to be.”