This is a real hot potato for anyone in the "establishment" to handle. It almost works best if it's not endorsed by the mainstream. As long as the Dem's intimidation tactics don't succeed, and this ad stays on the air, then I think all is well. People will see it and will be affected by it.
The only exception to this would be if the Republicans come out and blast the ad as false. But they have been quite careful NOT to do that; rather, they simply repeat the mantra that "we have never questioned Kerry's military service and we won't start now."
I suspect that in the future, this will take a place alongside the Willie Horton myth as a false example of how low Pubs will go. But that myth hasn't really hurt us, IMO.
See my 657. The Administration called it "deplorable".