When McCain shows me he is serious about national security, i.e. illegal immigration, and acts like he wants Conservatives to vote for him, perhaps some will.
So illegal immigration issue = national security? Nothing more to it than that? Right.
Personally not having a President who will deliberately lose another war - to jihadis no less - is pretty important to me. Not to mention things like his positions on national defense.
If people are worried about what Obama will do, they should focus those feelings on Obama. If McCain wants Conservative support, he knows how to get it. If he doesn't want it, he doesn't deserve it.