ABC’s Jon Karl reports on Senator Portman’s tough talk:

He’s polite, smart, and a little nerdy. But as Rob Portman has climbed to the top of the list of potential running mates for Mitt Romney, the political world is now seeing a different side of him: the attack dog.

Karl goes on to list a few of Portman’s recent slams, such as calling the president a “celebrity,” “out of touch,” and a peddler of “poll-tested platitudes.” Portman’s office denies that the comments are part of a veep campaign.