Sen. McCain would be a problematic candidate, at best, as this thread shows. I'd be willing to hold my nose and vote for him, but I doubt that all that many social conservatives would come along for the ride.
However, Sen. McCain would likely fare much better than Mr. Giuliani in that regard.
The Republicans should nominate an actual conservative, rather than mavericks or liberals.
That would be a tough one. I think voting for McCain would require a Scuba mask and a couple of full tanks of oxygen.