I can't see that it will impact the election in any significant way, GG. Them what was gonna go Green will still do so. IMO, people will want to see a Dem in, and this election I don't think too many voters will fall into a 'protest vote' vortex. He helped get Bush re-elected (imo, elected for the first time), and most folks won't forget that.
Of course, I've been wrong before and won't be surprised if I'm wrong again.