Nate Silver, whose website had the most accurate predictions for the Nov. 4 vote for president and senators, has a new prediction: Al Franken will win the Minnesota Senate recount — by 27 votes.

Franken came in 215 votes behind incumbent Republican Norm Coleman on election day, in an election where 2.9 million votes were cast. Under Minnesota election law, a hand recount was mandatory and began last Wednesday.

Silver, a sports statistician who turned his formidable mathematical talents to evaluating political polls for the 2008 election, became a legend among political junkies when his final prediction for the Nov. 4 election accurately predicted the winner of 49 of the 50 states. He forecast that Obama would beat McCain by 6.1 percentage points; Obama won by 6.8 points. Silver also correctly predicted the winner of every Senate race (except for Minnesota, which has not yet been settled).

Silver’s methodology relies on multivariate regression analysis, well-known to statisticians but difficult for non-specialists to grasp. In this case he is analyzing precinct-by-precinct returns available on the Secretary of State’s website, and focusing on the number of challenges from each camp. He released his projection Sunday afternoon.

The law governing recounts in Minnesota is excellent. The state has a complete paper trail for all ballots and a uniform system of counting for all counties (unlike Florida in 2000). If any intent on the part of the voter can be discerned, the ballot must be counted.

Disputed ballots will be adjudicated by a five-person state panel consisting of the Secretary of State and four judges. The Secretary of State is a Democrat; two of the judges were appointed by a Republican governor, one by an independent, and one elected in a non-partisan election.

Minnesota’s ballot requires that voters fill in a circle next to the candidate’s name. Machines read the ballots but fail to count votes indicated by check marks, X’s, circled names, or other marks. Experts had predicted that Franken would pick up more votes in the hand count because Democrats were more likely to mis-mark their ballots – because they were first-time voters or less educated.

Since the law requires that any discernible intent of the voter be counted, those experts predicted that Franken would win. But they lacked a firm statistical basis for their prediction.

When got almost five million page views on Election Day, the New York Times called Silver "perhaps the most unlikely media star to emerge" in 2008. He was also featured in the Wall Street Journal, Newsweek and the New Republic, and he appeared on The Colbert Report and the Rachel Maddow Show.

The race has special significance for Democrats: it’s for the seat of legendary liberal Paul Wellstone, who was killed in a plane crash a week before election day in 2002. If Franken goes to Washington, the Democrats will have 59 seats in the Senate – close enough to the 60-vote filibuster-proof majority they have been dreaming of.

As of Sunday night at 800pm, the official recount had Coleman ahead by a whopping 25,000 votes, with about two-thirds of the ballots recounted and each side challenging about 950 of the other’s ballots. That seems like a significant lead for Coleman, but Silver is sticking by his prediction.