Rep. Ken Buck (R-CO), a member of the hardline House Freedom Caucus, has upset other right-wing lawmakers recently by sounding cautious about efforts to impeach President Joe Biden.

CNN reports that "there is a serious effort underway to find a candidate to mount a primary challenge against Buck in his solidly red district in eastern Colorado" despite the fact that Buck has long been one of the most conservative members of Congress.

Rep. Marjorie Taylor Greene (R-GA), who has literally been trying to impeach Biden since his first day in office, told CNN there is a great deal of frustration with Buck, who has a prominent seat on the House Judiciary Committee.

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"This is the same guy that wrote a book called ‘Drain the Swamp’, who is now arguing against an impeachment inquiry,” Greene fumed. “I really don’t see how we can have a member on Judiciary that is flat out refusing to impeach. … It seems like, can he even be trusted to do his job at this point?”

However, Rep. Diana DeGette (D-CO) told CNN that she believes Buck is speaking up for many members of his caucus who are reluctant to impeach Biden given the lack of direct evidence showing that he profited from his son's overseas business dealings.

"I think a lot of the Republicans feel this way," she said. "He’s coming out and saying publicly what a lot of Republicans are saying privately."