Will McCain do that? To some degree, probably yes.
Will Sarah do it? She's someone who "walks the walk"; she'd have to essentially surrender her core beliefs to abandon social conservatives. No, I think Sarah will remain solid.
So, let's see if taxes and government spending are under control in 2012. School choice would face fierce opposition from a Democratic majority in congress. Supreme Court appointments will be a key factor.
No expectations for immigration reform. Who gets important cabinet positions will be another factor.
Even if McCain wins, it's still an uphill battle for conservatives. It's not at all clear Palin becomes a front runner in 2012. Not every VP turns into presidential material. Just ask Quayle and Gore. Or Mondale.