Seeing that Al Sharpton is going out of his way to criticize John Edwards, it is fairly clear the motive. (no links- quick post before I hop out; but I'm thinking of 1) his first comment in the last debate was an attack of Edwards' two nations speech, and 2) in NY, Sharpton said recently that Edwards' citing that he wins over indies and repubs is misplaced- Sharpton says Dems shouldn't be concerned with winning over swing voters)
Clearly, Sharpton wants to win delegates so he has a place in the Boston convention. The person that chooses such places is the nominee. If you want a place, then, best kiss up to him that you think will be said nominee. Sharpton is doing the dirty, negative work for Kerry hoping to win some favor.
I think, right now anyway, that this is unsolicited from Kerry. Rather, I think Sharpton is just being an opportunistic meanie right now and ought to lose any respect that his punch lines have afforded him up til now. Shame.