An Obama supporter was trying to make the case to me yesterday that the real advantage Obama would have vis-a-vis his Democratic rivals (but especially John Edwards in this instance) in bringing about change is not so much his ability to bring people together in the micro sense (sitting around the negotiating table) as his ability to bring people together in the macro sense -- drawing huge crowds around the country, building this vast base of small donors, etc. That stuff gives him levers that can be pushed to create constituencies for change and generate pressure on legislators.
This is pretty plausible to me. Certainly, Obama is the politician in the race with the most talent, the most upside. You can imagine his working incredible wonders, if he plays his cards right. On the other hand, he hasn't always done that. Meanwhile, I agree with Clive Crook and Matthew Cooper and Felix Salmon that there's not much in the way of clear policy contrast between the two and I don't see any clear reason to think that Edwards' rhetorical approach will produce larger gains than Obama's. Indeed, Obama's seems much better-suited to a general election campaign, and it's by winning the election that you create the circumstances where change is possible.
Now for the sake of my sanity, I think I need to stop thinking about the Democratic primary.
Photo by Flickr user Allison Harger used under a Creative Commons license