Could There Be a Viable Post-Ron-Paul Peace Candidate?

In his brand new book The End of War, John Horgan argues that war isn't inherent in human nature and can disappear if enough people want it to disappear. I just did a Bloggingheads dialogue with Horgan, and we wound up discussing whether there could ever be a plausible 'peace candidate' for president (which leads us, in the last couple of minutes of this clip, to a discussion of the role of religion in war and peace):

On post-dialogue reflection, I fear that a viable third-party peace candidate is unlikely. The natural constituency would consist mainly of (a) Republicans who are very fiscally conservative, including libertarians; and (b) Democrats who are in the left wing of their party not just on foreign policy but, typically, on domestic policy. It's hard to imagine a domestic policy platform that both groups could stand on. Anyway, back to Horgan's book: It's a brisk, uplifting read. Here's an excerpt that just appeared on The Atlantic.