Other assessments of the Massachusetts polls and voter turnout from around the web:
Suffolk University shows momentum for Brown in a poll of bellwether counties.
Nate Silver sees Brown as a 3:1 favorite, gives Coakley a 25% chance of winning.
Harry Enten shows Brown winning regardless of turnout.
Gallup finds the same percentage of Democratic identifiers in Massachusetts as the nation.
Martha Coakley says the polls are wrong.
So Does GregR at Blue Mass Group.
Jim Geraghty notes Brown's support among Democrats.
Reid Wilson looks at the stakes for pollsters.
PS: As I noted a few days ago on Twitter, the networks are not be conducting an exit poll in Massachusetts today. Network interest in doing one, I'm told, occurred too late for the long lead time necessary. We'll probably live-blog again tonight...check back in later for details.
The Cook Political Report's David Wasserman suggests some bellwethers to watch.'
Mark Ambinder posts a "what to watch for" cheat sheet with links to websites reporting results.