The vote on Plan B was perhaps the most consequential test of Boehner’s leadership since he took control of the House early last year. Persuading a majority of Republicans to cast a politically treacherous vote to allow higher taxes could have enhanced his leverage with Obama in future talks to rein in the national debt, Republicans said. But failure could imperil his hold on power, said Craig Shirley, a Republican consultant who wrote a biography of former president Ronald Reagan.

“If this was a parliamentary system, tonight’s dissent on Plan B would be seen as a vote of no confidence in Boehner,” Shirley said. “The national GOP is now simply a collection of warring tribal factions.”…

“The Republicans are in an untenable situation,” said Rep. Dan Burton (Ind.), who was leaning toward supporting the measure Thursday. “If we don’t do anything, we go over the fiscal cliff. And then the president will come back . . . and if the economy goes to hell, he’s going to say it was the Republicans’ fault.”

But Rep. Allen West (R-Fla.), serving his final days after losing his reelection bid in November, said the GOP brand would suffer if Republicans took a step that they had long argued amounted to a tax increase. “If you don’t draw a contrast with the other side, who are you?” he asked.