Despite the probably validity that, as Joe Conason relays, Al Sharpton is fronting a Republican consultant, I'm not sure that invalidates what Sharpton has to say. It's harder to believe he'd abandon his own rhetoric, much of which is old-fashioned Democratic meat and potatoes, than it is to believe he would take support from whatever quarter to keep himself going. I'm not arguing ego has nothing to do with it -- far from it -- but the possibility of this being a Republican dirty trick has to be mitigated with the possibility Sharpton may energize more people to vote Democratic in the fall. Either way, I'm sure the eventual nominee is not going to have much of a problem distancing himself from Sharpton as necessary, and if this is the latest Lee Atwater race-bait, it's not that well thought out.
For Sharpton's part -- this is pure speculation here -- he may well believe he's pulling a fast one by getting Republicans to pay for his bully pulpit. I'm not sure who's being stung here, but I'm certain it's a low-stakes con.