Sen. Arlen Specter (R-Pa.) leads TV host Chris Matthews (D) by just 3 points, 46%-43%, in a hypothetical 2010 Pennsylvania Senate race matchup, according to a new Rasmussen poll.

Matthews, a Philadelphia native, has not announced that he's running, though he's been advised to quit his MSNBC gig if he's serious about it, Politico reported today. If he were to run, he'd have a tough Democratic primary to get through before taking on Specter, the five-term incumbent.