You mean if he runs as an independent? I don't see it. He would have to get on the ballot in all 50 states to have any shot. He won't have time to do that and won't have enough money to win, absent some Ross Perot-type writing checks for him.
If he overcame all of those obstacles and ran as an independent, there is precedent for him causing problems in the general. Nader is partly responsible for Gore losing in 2000 (took votes in Florida). It's possible Paul could siphon votes from the Republican nominee next year in a critical state, but I'll be surprised if that happens.
Nader attracted the far LEFT votes, which took away from Gore.
Paul has a LOT of hardcore far RIGHT beliefs. He'll steal way more republicans than dems, which will help the dems. He won't win, but if he takes votes in 3 states, he just giftwrapped the election for Miss Hilary.
And of course, a Paul-Bloomberg ticket WOULD have the cash to make a huge mess of things. Big big moise lately about Bloomy planning a run as an independent. Paul would be a gift for Bloomy. ALl his money plus all the Ron Paul love...