Looks like former congressman Bob Barr is going to
get in the race as a Libertarian. I think it's safe to say that he won't be elected president. That said, I think there will probably be a bunch of voters who don't much like the McCain Perpetual War agenda but who also think that at the end of the day Barack Obama's a liberal and they're not not. In theory, at least, there's room for a sort of John Anderson figure and you could see Barr playing that role.
This article available online at:
http://www.theatlantic.com/politics/archive/2008/04/the-bob-barr-era/44169/