Here's another good top-10 list: techPresident's Favorite Videos of 2007: The Candidates.
I agree with seven of these as top-quality, although the actual rankings seem a bit random. I wouldn't have made #1 the top choice or necessarily included it at all. Not that it's a bad video, but is it really top-10 material, much less #1? And what's with #9? (And #8 is a good clip, but it's not a campaign video at all.)
As for my top choice, I might have put Bill Richardson's ad as #1—certainly in the top 3. It's much better than the candidate, who looks worse the more you see of him.