I had occasion to speak with Sen Casey while in DC at one of our 2009 protests. I found it rather disturbing. He repeated talking points and platitudes and would not engage in anything resembling conversation. To his credit, he can speak in complete sentences without using a teleprompter, but he doesn't come across as having any independent thoughts or forming conclusions based on any sort of analysis. He had nice shiny shoes and a nice suit though . . . he looked the part.
I notice that whenever he travels in the Commonwealth, his handlers are careful to ensure that he doesn't interact with average citizens, at least beyond the photo-ops and superficial pleasantries.
I'd be surprised if it was any different in DC. For all Specter's faults, I do give him credit for not being afraid of his constituents.