Republican Rep. Jason Chaffetz, chairman of the powerful House Oversight and Government Reform Committee, will launch a run for speaker of the House, NBC News confirms.
The Utah congressman's entry into the race — which he will officially announce Sunday — sets up a contentious fight for the speakership with House Majority Leader Kevin McCarthy, viewed as the overwhelming front-runner.
Some Republicans have become wary of McCarthy's chances in recent days following his comments indicating the House Select Committee on Benghazi was formed to hurt Hillary Clinton's presidential campaign rather than to investigate the 2012 attacks in Libya that killed four Americans.
"Everybody thought Hillary Clinton was unbeatable, right? But we put together a Benghazi Special Committee, a select committee. What are her numbers today? Her numbers are dropping," McCarthy said on Fox News Tuesday.
McCarthy since clarified his remarks, saying he did not intend to suggest the Congressional investigation is political.
Chaffetz has been critical of his GOP colleague following the comments, but previously indicated he still supported McCarthy.
"I'm very supportive of Kevin McCarthy, but those statements are just absolutely inappropriate, they should be withdrawn, Mr. McCarthy should apologize,"Chaffetz said on MSNBC on Thursday.
POLITICO first reported Chaffetz' surprise run on Friday. His office would not respond to repeated requests for comment.
Conservative Rep. Daniel Webster (R-FL) is also a candidate for speaker.
Republicans will vote on leadership positions Oct. 8, but no date has been set yet for the entire House to vote for speaker.
This article first appeared on NBCNews.com.