One big difference is that Romney has worked for a living, become a self-made multimillionaire and actually pulled the most liberal state in the nation halfway out of the toilet, though it seems determined to get right back in.
Meanwhile, Obama's career consists of being a "community activist", being handed a professorship and gliding from one elective office to the other.
While Duncan Hunter remains my first choice of the declared candidates, I'm willing to give Romney a look if only to slow the McCain trainwreck the party bosses seem headed for.