Well, Obama certainly has a lot of momentum going right now with his big win in South Carolina this week. The endorsement's certainly help out, though I don't think most people change their votes based on that. (It just lends legitimacy.) However, and maybe you just don't get this in your news, Clinton has two victories under her belt and actually has a higher delegate count right now.

Edwards hasn't won a contest yet, but he's still putting up respectable figures as well. There's been some talk that he could end up being very important if the race is still undecided by the convention.