I think it is pretty clear that having Nader in the 2000 election cost Gore the presidency. Yes, Nader got votes from both Dems and Reps as well as Green, Independents, etc...but the majority of those voters who would choose to vote at all, would have gone to Gore. That being said, Gore ran one of the worse campaigns in modern Presidential politics (right up there with Dukakis) and he and his campaign are ultimately responsible for the loss.
Now, I do not think that Nader will play quite as much of a factor in 2004. Dems and Libs in general are pretty dissatisfied with President Bush and most won't do the "I'm voting my conscience" routine. However, barring any major events, I think this is going to be a very close election and every vote will count. So Nader may yet have a role to play.
I have a suspicion that Nader is simply trying to ensure that some of his issues are addressed by the candidates and that as the election gets closer, he will gracefully back out and support the Dem. (Actually this is probably a long shot, but I can always hope.
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