None of the major labor unions have taken sides in the primary, for a range of reasons. Some were burned by going early for Dean in 2004. Many leaders like Edwards, but aren't sure he's popular enough with the rank and file, or likely enough to win, to risk an endorsement.

Anyway, Jonathan Tasini — a labor movement insider who heads the Labor Research Association in New York — has predictions of which candidate each union will go for. Perhaps unsurprisingly, he sees many for Edwards, and few for Obama.