Let's see....spend a couple hundred million on a campaign (which he'd probably lose), or make a couple hundred million from a reality TV show where he donates millions to charity?
He's an attention whore. Running for president would bring only bad attention that his fragile ego couldn't handle. He's better off as a reality TV star so he can do whatever the hell he wants and not have to get torn to shreds in the media.
Republican voters pay attention to Republican comedian entertainers (Palin, Bachman, Gingrich, Trump, Huckabee) and ignore the colorless real candidates (the guy from Utah, the guy from Indiana, the guy from somewhere around Minnesota...I can't remember any names because I hardly ever read about them...oh yeah, Pawlenty or something is one...)
Let's get to the real reason he isn't running for office . . . . . . . . he can't find his birth certificate.