WASHINGTON (AP) -- In a stunning move, Majority Leader Kevin McCarthy withdrew his candidacy for House speaker Thursday, throwing Congress' Republican leadership into chaos. McCarthy was heavily favored to win his GOP colleagues' endorsement for the post, but a vigorous challenge from hardline House conservatives threatened a smooth ratification when the full House voted Oct. 29. It is uncertain now when that vote will occur to replace Speaker John Boehner, who is to retire at the end of the month.
McCarthy shocked his colleagues at the start of Thursday's closed meeting, telling them he was not the right person for the job. He recommended that the election be postponed and Boehner delayed it.
"There was total shock, and then total silence," said Rep. Robert Pittenger, R-N.C.
Lawmakers were in near disbelief at the announcement, which came as Republicans began a meeting for what they thought would be the election of a new speaker nominee.
"I've never seen anything like this," said Rep. Ryan Costello, R-Pa.
Rep. John Fleming, R-La., said he was "thunderstruck."
"We don't know why he did it," said Rep. Mick Mulvaney, R-S.C.
McCarthy's decision plunged the House GOP into further turmoil, just weeks after Boehner's decision to resign had left Republicans reeling.
Just hours earlier, McCarthy and his two rivals to replace Boehner addressed a closed-door meeting of the GOP rank and file in the basement of the Capitol, making final pitches ahead of elections.
Rep. Kevin Brady of Texas, who supported McCarthy, said the 50-year-old Californian pitched himself as "a proven leader, a generational change in the speakership."
"Plus he listens very carefully," Brady said, "and as a result our conference will continue to have more power over the agenda, which is what we all want."
But McCarthy had failed to win over a small but crucial bloc in the House GOP: the hardline Freedom Caucus. This group of 30-plus uncompromising conservatives drove Boehner to resign by threatening a floor vote on his speakership. On the eve of Thursday's vote they announced they would oppose Boehner's No.2, McCarthy, and back one of his rivals instead, Rep. Daniel Webster of Florida, a former speaker of the Florida House.
That was a blow to McCarthy, although there had been little expectation that the group would back the Californian.
"Power doesn't like to give up its power, and so that's why many of us have gotten behind Mr. Webster," Rep. John Fleming of Louisiana, a Freedom Caucus member, said outside Thursday's meeting. "We feel that conservatives have been greatly marginalized by the current leadership."
Despite the opposition, McCarthy clearly had been expected to emerge the winner Thursday over Webster and a third rival, Republican Rep. Jason Chaffetz of Utah, who chairs the House Oversight and Government Reform Committee. That would have made McCarthy the House GOP nominee for speaker.
But his true test will come Oct. 29, when the full House will vote for speaker in open session. With Democrats certain to back Minority Leader Nancy Pelosi, a Republican will need to win a 218-vote majority to prevail.
If no candidate wins that majority, it would send the House into uncertain territory.
It hasn't happened in decades, but in years past speaker elections have required multiple ballots before any candidate prevailed. Some of the more establishment-aligned lawmakers are voicing fears about such an outcome on Oct. 29.
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