I've already stated that I believe Gen. Wesley Clark is running for President for the Republican Party (OK, maybe it is really the DLC, Republicans-Lite), because they realize that G. Walker Bush is not going to win re-election.
I also believe that a meeting held between Howard Dean and Clark included a conversation suggesting that if Clark lost, he would happily be Dean's Vice-President.
Adding these two together implies that a Dean/Clark victory in 2004 would spell a short lifespan for Mister Dean. I believe that right-wing extremist groups, or people posing as them and actually working for people behind the scenes in Government, would off Dean as soon as reasonable.
That is why I support a Dean/Graham ticket, and part of the reason, I suspect, Graham withdrew was in fact pressure from these same groups (who saw a Dean/Graham ticket as both potentially winning AND less alterable via assassination).