Name one.
Irrelevant anyway. Kerry can only stay afloat as long as he keeps America's eyes off his Senate record. Among other things.
What everyone fails to realize is that Bush has been inoculated by the mudslinging 2000 race and three years of massive efforts to ruin his administration. What dirt there was, if any, is pretty much out there. Kerry has only just now entered that gauntlet, fed by the Republican activists and the Argus eye of the internet, and there's eight long months until the election.
Good luck!