If Not Arlen, Then Who?

It’s still early for battle lines to be drawn, but one PA Dem who has made noises about possibly taking Specter on in the primary is former admiral, now Congressman Joe Sestak.  Polling guru and a fav of mine Nate Silver hypothesized the other day that Sestak is actually less moderate than Specter, but Sestak constituents have come roaring back (via TPM):

Sestak is my rep. Nate might be an electoral-poll god, but he is way off on this. He cites silly ratings in his piece that don't reflect reality. There is NO WAY Joe Sestak, had he been a Senator, votes for the Bush tax cuts, or Roberts, or Alito. Sestak voted for Obama's budget; has an excellent labor record, and is superior Democrat in every way to the principle-free Specter. I work in an office in Sestak's district that is 25-5 Democratic, and for years I've been pleading with people to take a hard look at Specter, whom they have consistently given a slide to as some sort of 'moderate.' Someone the other day said, "Yeah, he's a weasel, but he's OUR weasel.' And this person should know better. Very frustrating. Arlen self-preserves with this move, and the Old Boys Club applauds (Biden, Rendell, the execrable Reid, all the way up to Obama). 'Clear the primary field' my ass. I'd love if Sestak took Specter on and kicked his sorry ass.

And, from a not so enthusiastic constituent:

I'd have to agree with the first responder. Sestak is my representative as well. I donated money and worked hard for him in 2006. In 2008 I did neither because on some issues important to me (the war and whether anyone in the white house should be punished for criminal actions) he was a big disappointment. He's very middle of the road on many things. However, if he opposed Specter for the nomination I'd donate and work for him again because he would be a *much* more reliable vote for so many important Democratic issues. There's just no contest.

Arlen Specter thinks he's a middle of the road moderate because he says one thing and then votes the opposite and he believes that somehow balances things out.

Can the Pennsylvania residents of this readership offer any insight of their own?  Nate Silver throws Franco Harris out as a possibility.  Really?