From NBC's Domenico Montanaro
Underway in Maine, from today through Sunday, are its 413 Republican municipal caucuses. At the end of each meeting, voters will indicate their preference in a straw poll, with which the state's delegation, for the most part, will base their voting at the national convention (though all of their 21 delegates are completely unbound).
Even though the caucuses continue through Sunday, the Maine state GOP says it will announce the results of the straw poll Saturday night. The majority of its precincts wrap up Saturday and because the Patriots are in the Super Bowl, fewer precincts are holding caucuses on Sunday.
Those 21 delegates (plus 19 alternates) are are whittled down from 3,000-plus municipal delegates, which are selected this weekend. They then go to the May state convention where they are narrowed to just the 40. At the state convention, they will all agree (or not) to vote for the same person at national. But if there's a strong contingent of delegates who are for McCain and a strong contingent who are for Romney, for example, then they could go to the national convention with a split delegation.