He won't. He doesn't have what it takes to do that.
I will give him the benefit of the doubt until just before election day -- if he can stir his fans up into voting for the recall, he will be providing a service -- but he should endorse Arnold the day before, and if he was smart he could use the smear campaign to finesse the policy/ideology differences he has w/ Arnie -- he can point at the Demosleaze attack and say "...we need to teach sleaze artists a lesson, so i ask my fans to hold their nose and vote for Arnie..."
It remains to be seen if McClintock is wise enough to do this...