This has been noted as being almost like a game of rock-paper-scissors:
Some other numbers for Specter: 46/52 favorable/unfavorable (Rasmussen); 31/59 deserves-reelection (Susquehanna). The Susquehanna poll also has him leading Sestak in the primary 44/16 and tied with Toomey 42/41, but that may be the usual registered/likely voter difference. All in all, it's starting to look like maybe Specter should have taken the hint and announced that he wasn't going to run for re-election after he switched parties...
Crossposted to Moe Lane.