Re: ISH, let's get political: Barack or Mitt?
They are different, and most importantly they'd operate in different contexts.
Romney, while more of a a moderate himself, would have to deal with the Republican base of angry white males. He would soon be perceived as untrustworthy, as he'll have been elected by people whose beliefs he doesn't really share.
He would also be surrounded by more Bush-style neocons.
Finally, lobbyists would regain influence, as would Wall Street.