Why Kevin McCarthy Dropped Out of the Speaker's Race

House Majority Leader Kevin McCarthy made up his mind to pull out of the race to be House speaker this morning after hearing from chamber conservatives that they would directly challenge him on the House floor, sources say.

McCarthy's team determined he only had 175 to 200 House Republicans whom they could count on voting for him, well short of the 218 needed.

The California Republican, 50, had the support of the overwhelming majority of House Republicans - about 75 percent of them - but the conservatives refused to say they would unite behind him, the sources told ABC News.

So a narrow minority has effectively hijacked the process. They don't have the votes to elect their own candidate but they have proven they can block a candidate they don't like.

McCarthy determined that even if he could get the 218 votes and be elected speaker, the conservatives would continue to challenge him, making it effectively impossible to lead the House.

"He thought he would have a honeymoon," a McCarthy confidant told ABC News. "It became clear there would be no honeymoon."

McCarthy also surmised that he'd be unable to lead the House through the serious challenges this fall, especially funding the government and preventing a U.S. default on the debt, the sources said.

What's next?

"Total chaos," one top Republican close to the House leadership told ABC News today.

Rep. Paul Ryan of Wisconsin, chairman of the House Ways and Means Committee, was the most likely one to unite the House Republicans, but he says he won't be a candidate.

Rep. Trey Gowdy of South Carolina, now busy with the Benghazi committee, is being asked to run. He has said he has no interest in the job.

After Gowdy, Rep. Jeb Hensarling of Texas is another possibility, although he has said he didn't want to take leadership for family reasons.

In other words: More chaos ahead.