CNN has just called it, and it looks like he's going to win by a hefty margin. It would have been nice to see some entrance poll data, but, alas, there isn't any.

My hunch is that the Clinton campaign didn't make much of an effort to turn out its supporters today. There are enough white working class people in Maine to have made it relatively close. (Unless Obama has started to make some real inroads among the white working class--again, would have been nice to see demographic data.)

--Noam Scheiber