Unlike the Democrats who tell people who can't lose to get off the stage, Republicans will do nothing and McClintock will try to steal the spotlight until the end (instead of supporting Arnold and trying to influence Arnoldn's policies). Republicans may not believe in abortion, but California Republicans are expert at eating their young (and doing their own cause in in the process). Literally, they would rather be "right" than "elected".
You don't think that by staying in at this point he's influencing Arnold's policies?
But the moment McClintock leaves the race, Shwarzenfathead will have NO incentive to listen to conservative views but will arrogantly ignore everyone but his fawing liberal advisors as his sycophants and toadies croon his praises in the moonlight.
This is not too different than the 19 Muslims who choose to be "right" rather than "living" on 9/11.