I suspect McCain's reason for picking amnesty and global warming -- as opposed to sae the whales and legalizing pot -- could be summed up as "What can I do to piss off conservatives?"
He seems incapable of sticking the knife in without twisting it.
not to mention lying during the contested part of the primary. He must have called himself a conservative 500 times while he was fending off Mitt and the boys. I have not heard him utter the “c” word since.