Republican Rep. Ken Buck leaves Congress next week, reducing GOP majority.

Denver — Colorado Republican Rep. Ken Buck announced Tuesday that he will resign next week, lowering his party's razor-thin House majority and possibly thwarting Rep. Lauren Boebert's bid to succeed him.

Buck, a conservative who had declined to run for reelection as he grew increasingly critical of his party's handling of former President Donald Trump, made his surprise announcement during the House Judiciary Committee's hearing on Special Counsel Robert Hur's investigation into President Joe Biden's handling of classified documents.

Buck complained on that he hadn't been able to pose a question in the hearing despite being the committee's third-ranking Republican. Much of this is personal. That’s the issue, Buck added. He said this was the worst of his nine years in Congress because “instead of having decorum — instead of acting in a professional manner — this place has really devolved into this bickering and nonsense.”

Buck's March 22 resignation will decrease the GOP's House majority to five seats and force a special election to finish his term. Colorado law requires it to be held in mid-to-late June, and Democratic Gov. Jared Polis announced Tuesday afternoon that he would hold it on June 25—the same day as the Republican primary to replace Buck in November.

Boebert is one of numerous GOP primary candidates to replace Buck. She moved across Colorado to seek for Buck's eastern plains Republican seat. A committee of Colorado Republicans must choose a nominee for the special election held the same day as the primary before district voters vote.

Political experts speculated Tuesday that the controversial Boebert, who had no past ties to the district and has angered many Republicans with her campaign, would not be the nominee. That means only one Republican will face the Democratic nominee on the June 25 special election ballot. Many conservative voters in the district will likely vote for that individual to ensure the GOP replaces Buck for the year.

They'll next vote in the primary, where the Republican nominee they just voted for and Boebert will presumably run. That provides the party committee's choice a huge edge in the primary. Buck told Capitol Hill reporters Tuesday that the local Republican chairman might choose his heir.

Whoever takes that position for the next Congress and the rest of this Congress will do well, he said. Buck indicated he intends to stay in politics after resigning. “I just feel there is important work to be done concerning the election and how we choose candidates,” Buck said. “I want to get involved in this election cycle and make sure we choose the best candidate.”

Buck is an ultraconservative House Freedom Caucus member and former federal prosecutor and northern Colorado district attorney. Since the 2020 election, he's been known in Washington for opposing his party on critical topics. He supported certifying Biden's presidential victory and opposed Republican efforts to impeach him and make Trump supporter Rep. Jim Jordan speaker.

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