Did the Republicans set up John McCain to be the fall guy for Bush's failures?

The theory is this. The GOP knew that they were doomed to lose this election after the failures of the Bush administration. They didn't want to waste one of their good candidates, so they allowed McCain to get the nomination. He's not really a Republican anyway, so this way they can hang the anchor around his neck for losing the election, and come back in 4 years with Mitt Romney and a re-organized party.