Most elections in the U.S. are what we call “first past the post” — that is, you vote for one person, and the candidate with the most votes wins, even if it’s not with a majority. Not so with ranked-choice voting, also called instant-runoff or preferential voting. In races with more than two candidates,1 Maine’s new ballots ask voters to rank candidates from their first to last choice. If no candidate receives a majority of first-place votes, the candidate with the fewest first-place votes is eliminated, and his or her supporters are redistributed among the remaining candidates based on whom they ranked second. If still no candidate has a majority, the candidate with the next-fewest first-place votes is eliminated, and so on until someone wins 50 percent plus one vote.

This procedure ensures that no candidate opposed by a majority of voters wins anyway thanks to a fractured opposition, and it also makes it much safer to vote for a minor candidate without worrying that he or she will play spoiler. However, research has shown that ranked-choice voting also depresses turnout by making voting more complicated; indeed, Maine election officials are bracing for a surge in questions from voters unfamiliar with how to fill out the new ballots (which look like a grid). The secretary of state has also tried to combat voter confusion with posters hung in polling places, an animated video explaining how ranked-choice voting works and a web page of ranked-choice voting resources. The stakes of implementation are high: If Maine’s experience with ranked-choice voting is seen as a failure, it could hinder the campaign to expand ranked-choice voting even further. So far, anecdotal evidence is mixed on how well poll workers are prepared to sail these uncharted waters.