WASHINGTON — In a stunning move, Majority Leader Kevin McCarthy on Thursday withdrew his candidacy for speaker of the U.S. House.

GOP lawmakers said McCarthy told colleagues at the start of a closed meeting that he was not the right person for the job. He recommended that the election be postponed and Speaker John Boehner delayed it.

McCarthy had been heavily favored to be nominated by his fellow Republicans, but Thursday’s secret ballot — even if it had proceeded as expected — still would have been merely an early skirmish in the chaotic battle to lead the House.

As the day began, McCarthy and his two rivals to replace outgoing Speaker John Boehner were to address the meeting of the GOP rank and file in the basement of the Capitol, making final pitches ahead of elections to begin at noon.

Despite his lead over other candidates, 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.

The decision was a blow to McCarthy. Although there was little expectation that the group would back the Californian, there was much speculation that the sometimes disorganized hard-liners would be unable to rally around any of his opponents, either.

“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.

Associated Press writers Andrew Taylor and Alan Fram contributed to this report.