RCP on new Pennsylvania Senate survey from DailyKos/Research 2000:

Finds Specter back in the lead by 5 points (Aug 10-12, 600 LV, MoE +/- 4%). He also leads by 15 points in the Dem primary against Rep. Joe Sestak — who leads Toomey by 1 point in a general election matchup.
Specter’s 52% favorability rating is 15 points higher than both Sestak and Toomey, and 9 points higher than the Rasmussen survey found. Against Toomey, Specter wins 43% of independents, 3 points more than Toomey.
Dem Primary
Specter 48
Sestak 33
Und 19
General Election
Specter 45
Toomey 40
Und 15
Sestak 42
Toomey 41
Und 17
Specter leads Sestak by 20.0 points in the RCP Average for the Dem Primary. Toomey leads Specter by 2.0 points and Sestak by 3.7 points in the RCP Averages for the General Election.