Voter turnout is on track to be heavy in Maine today, where a referendum on gay marriage has spurred intense political activism on both sides.

Secretary of State Matt Dunlap told TPM that turnout had originally been predicted to be about 35%, on the assumption that the heavy absentee and early voting -- about 150,000 ballots went out -- would take away from turnout on Election Day. "But apparently that's not been the case," said Dunlap, who has rethought his turnout predictions, saying it could reach 50% or even higher.

By contrast, typical off-year referendum turnout in Maine is 15%-25%, with the 35% number having been an estimate of how the increased interest in the gay marriage vote could affect things. Dunlap said that 50% turnout does have a precedent, as a vote on casinos reached 51% turnout six years ago.

One thing yet to be determined is what will happen between 5 p.m. and 8 p.m., when many more people will vote after work.

Dunlap said that there are no immediately apparent areas of disproportionately high or low turnout, but that we won't know for sure until after the election is over. One potential factor can be how local town referenda can spur extra votes in select areas: "Sometimes we miss those until we see afterwards, and try to figure out what caused an extra turnout in Wytipitlock."