Obama wins Maine

AP and NBC have called the Maine caucuses for Barack Obama, giving him a clean sweep of the five contests this weekend and denying Hillary Clinton one of her best shots at breaking his momentum and slowing the rate at which he's building a lead among pledged delegates.

With 70 percent of precincts reporting, Obama led the tally of state delegates by 58 percent to 41 percent.

Obama's victory comes despite being down in all four polls of the state, and despite his loss in the primary in neighboring Massachusetts. Clinton had been thought to have a strong shot at winning in Maine, whose demographics -- largely white, heavily working-class -- are those that have typically favored her. She also had the support of the state's governor, John Baldacci, and of his organization.

But Obama demonstrated his edge, yet again, in states decided by caucuses, in which the key factors are organization and the intensity of support. His supporters proved willing to trudge out in the Maine snow on a Sunday afternoon to support him, and they were rewarded with victory.

The Maine Democratic Party reported that with 78 percent of the results in, the turnout for the primary was 37,361 people; the state's overall population is 1.3 million. The final number appears likely to be less than the 53,000 people who turned out for the 2006 gubernatorial primary -- though the fact that a similar number of people turned out for a caucus and a primary demonstrates the intensity of the interest in this race.

Obama's prize: More delegates, and momentum headed into the Potomac Primary (aka Chesapeake Primary) Tuesday.