Rep. Ken Buck (R-Colo.) announced Wednesday that he will not seek reelection next year, putting a bookend on his congressional tenure that has most recently been defined by breaking with his own party and by his criticism of the belief among some Republicans that the 2020 presidential election was stolen. 

Buck’s announcement is a reversal from his previous plans — in September, he confirmed to The Hill that he was planning on running for reelection. 

“I have decided, Andrea, I’m not gonna seek reelection,” Buck said on MSNBC’s “Andrea Mitchell Reports,” adding, “I’ve decided that it is time for me to do some other things.” 

Buck, who was first elected to Congress in 2014 and represents Colorado’s 4th Congressional District, is the second GOP lawmaker to announce their retirement from the House on Wednesday. Earlier in the day, Rep. Kay Granger (R-Texas), the chair of the powerful Appropriations Committee, also announced she would not seek reelection. 

Buck’s district went for former President Trump by close to 19 points in 2020, meaning whoever wins the Republican primary next year is the heavy favorite to win Buck’s seat.  

The Colorado Republican — who is a member of the conservative House Freedom Caucus — referenced the election denialism that has percolated through his party when announcing his intention not to run for re-election. 

“Our nation is on a collision course with reality and a steadfast commitment to truth, even uncomfortable truth, is the only way forward,” he said in a video announcement. “Too many Republican leaders are lying to America, claiming that the 2020 election was stolen, describing Jan. 6 as an unguided tour of the Capitol and asserting that the ensuing prosecutions are a weaponization of our justice system. These insidious narratives breed widespread cynicism and erode Americans’ confidence in the rule of law.”

The decision by Buck, 64, came after the congressman — along with seven other Republicans and all Democrats — voted to oust former Speaker Kevin McCarthy (R-Calif.) from the top job, which plunged the House into a chaotic, three-week standstill.  

In a statement following the vote, Buck wrote: “It’s clear that we need a principled Speaker who can keep his word not just to members of Congress, but to the American people.” 

Buck was then one of the more 20 Republicans who withheld support from Judiciary Committee Chairman Jim Jordan (R-Ohio) as he mounted a bid for Speaker. He expressed concerns about Jordan’s involvement in efforts surrounding the Jan. 6, 2021, attack on the Capitol, and said he wanted the Ohio Republican to say that former President Trump did not win the 2020 election. Granger did not vote for Jordan either. 

Buck said his office had received four death threats over his refusal to support Jordan. He also said he was evicted from his office in Colorado because of his position against Jordan. 

Buck ultimately joined Republicans in voting to install Rep. Mike Johnson (R-La.) as the next Speaker, despite the fact that the Louisiana Republican voted against certifying the results of the 2020 election in Arizona and Pennsylvania. Johnson also spearheaded an amicus brief that backed a Texas lawsuit contesting the 2020 election results, which Buck said he signed on to. 

Buck argued the lawsuit was “fundamentally different than somebody who is actively involved in moving the protesters from the mall up here.” 

“The amicus brief is fundamentally different than trying to overturn something on the floor. What he did was, he went to the courts. That’s what the courts are set up for. It is absolutely appropriate. I signed that amicus brief, and I think it’s absolutely appropriate to go to the courts. The court said no, and I voted to certify the election,” he added. 

Buck himself voted to certify the 2020 election results — moving away from the 147 Republicans who voted to overturn some of the results — and said in mid-June he wouldn’t support Trump if he was convicted in a criminal trial. 

“If he is convicted of these charges of mishandling this information, of knowingly concealing his actions, I don’t think — I certainly won’t support a convicted felon for the White House,” he said on CNN. 

Asked on Wednesday if he would support someone other than Trump if the former president wins the GOP nomination, Buck said, “it’s gonna be a very difficult decision that I have to make if that is in fact the case.

“If it is a Trump-Biden re-do it is something that I’ll have to make that decision at the time. But I am not thrilled with either one of those candidates and we’ll just see what happens down the road,” he added.

Buck said the 2024 cycle is going to be “a critical election.”

“I think this election is gonna be a critical election, both at the presidential level and in the House. And I think people in the House are gonna have to make a decision on where they want to go with the values of the Republican Party,” he said.

Buck also levied criticism against members of his party over moves toward a House impeachment inquiry into the Biden family, particularly in September when Republicans struggled to break an impasse over funding the government. 

Colorado state Rep. Richard Holtorf (R) told The Hill in mid-September that he had formed an exploratory committee regarding his “political future,” offering at the time a potential primary challenge to Buck.  

Updated at 2:08 p.m.