“I can understand the supporters of the other republicans—even Ron Paul. I really don’t understand McCain supporters.”
Judging from that statement you must not place a lot of emphasis on the Global War on Terrorism or Iraq, of which McCain has the most credibility on.
Judging from your comment anyone who doesn’t like McCain is against the War on Terror. Judgements can be tricky things. :-)
The WoT is a huge issue, obviously. If management of the war were the only issue for a president, though, then I say we petition for Petraeus to run for POTUS.