It's a choice between two big government socialists.
I favor Obama on the basis of what he's achieved at such a young age, despite having absolutely no early advantages in life like a multimillionaire dad opening doors for him.
As far as McCain is concerned, he's clearly a brave man. My problem with him, is that I don't think America needs a gerontocracy at this point. If McCain gets in, the CIA and the Pentagon will continue to run the country for another four years, while an increasingly frail McCain will be wheeled out to wave at the crowds like Brezhnev used to back in Soviet Russia.