Heading into August retirement season, both the DCCC and the NRCC are going up with new radio ads today.

The DCCC spent a little of its treasure to begin running radio ads targeting a number of potentially vulnerable Republican incumbents, urging them to change their position on the war in Iraq. The ads are running against Reps. Chris Shays (R-CT 04), Mark Kirk (R-IL 10), Joe Knollenberg (R-MI 09), Mike Ferguson (R-NJ 07), Heather Wilson (R-NM 01), Jon Porter (R-NV 03), Jim Walsh (R-NY 25), Deborah Pryce (R-OH 15), Phil English (R-PA 03), Jim Gerlach (R-PA 06), Tim Murphy (R-PA 18) and Dave Reichert (R-WA 08). Hear the DCCC's ad here.

Not to be outdone, Republicans are tipping their hand a little. A spokesman for the NRCC tells RCP that Republicans will start running ads this afternoon against Reps. Paul Kanjorski (D-PA 11), John Murtha (D-PA 12) and Alan Mollohan (D-WV 01). The spots will focus on ethics. Ads will begin soon against Reps. Zack Space (D-OH 18) and Chris Murphy (D-CT 05), though a spokesman declined to release scripts.

UPDATE: An NRCC spokesman tells RCP that their ad buys total in the "tens of thousands of dollars" range, though further specifics are under wraps. A DCCC spokesman called their buys "significant," but did not elaborate.