On Election Day, Maine voters used an innovative voting method called ranked-choice voting (RCV) to choose the federal candidates on their ballots. After a court challenge and heated public rhetoric, RCV determined the outcome in one congressional race outcome for the first time in U.S. history. But it still faces significant opposition and limited use in the Pine Tree State. Maine became the first state to deploy RCV in its primaries back in June. While groundbreaking, RCV has been limited by state constitutional language stipulating that state legislative and gubernatorial general races must be decided by a plurality of voters. So, RCV was used only in the federal elections this time around. In Maine, that meant one U.S. Senate contest and two House races. Two of the three races were settled on election night, with Representative Chellie Pingree, a Democrat and Senator Angus King, an Independent, winning majorities. But in Maine’s largely rural, working class Second...