I can't imagine anything on this earth that would cause Cantor to challenge this position against Boehner. There isn't a line, so to speak. I'd actually be (pleasantly) surprised if any of our (R) reps have the spine to do it.
That’s the problem with my Rep as well - Tom Price of Georgia. He no longer votes for his constituents, and instead votes however Boehner votes. His August 2011 vote to increase the debt ceiling was the last straw. He is now dead to me. Conservatives don’t vote for debt ceiling increases. And conservatives definitely don’t vote to fund Obamacare. But Tom Price does.