If Boehner were to take on the tea partiers in his caucus, any one of them could force such a vote. Assuming the Democrats all voted in favor of the measure to dump Boehner as speaker, he could lose up to about 16 Republicans and still retain the position. But if more Rs joined the uprising, Boehner would be tossed. So one key calculation for Boehner—and for any mutineers-to-be—to consider is whether a rump group of Republicans could round up enough GOPers to vote him out of the top leadership post.
These rebels would have to depend on the Democrats voting en masse against Boehner. But would they really want to make common cause of that sort? Moreover, relying on the Dems would carry a risk. What if Rep. Nancy Pelosi (D-Calif), the House Democratic leader, were to play political mischief and instruct her colleagues to stand clear of the GOP civil war by not voting on the vacate-the-speaker measure? Presumably, the anti-Boehner forces would be crushed by non-tea-partiers. Of course, Boehner would then owe his speakership to Pelosi. Think of Javert being indebted to Valjean! Boehner might prefer to resign and enjoy slower days of golf and merlot. (How’s this for a backroom deal: Boehner brings a clean CR to a vote, and Pelosi agrees to help him hold on as speaker?)