On Wednesday, Maine became the first state in the country to pass ranked choice voting in presidential elections. The system is pretty straightforward: rather than casting a vote for a single candidate, voters will be able to mark their first, second, and third choices for president. If a candidate doesn't win with an outright majority of first-choice votes, the count moves on to the next tiers. Ahead of the 2018 midterms, Maine became the first state to allow voters to rank their choices in elections for governor, as well as senators and representatives at both the state and national levels.

Voting rights activists claim that ranked choice gives more power to citizens, and it would help keep a candidate from winning without securing approval from a solid majority. Every state has its own election policy, but in many places, a race with more than two candidates, and particularly in a field as comically crowded as the Democratic presidential primary, could easily produce a winner with well under 40 percent of the vote. Candidates with overlapping appeal can easily cannibalize one another's votes, preventing either from getting a plurality and effectively knocking them both out of a given race. In 2016, for example, Donald Trump won five states early in the presidential primaries with 35 percent of the vote or less.

Democrats in Kansas are also weighing whether or not to introduce ranked choice voting for the presidential primaries. Kansas is one of a handful of states that holds caucuses for its primaries instead of more typical elections where voters can arrive at any time of day, vote, and leave. The caucus system is more complicated and difficult to organize, and it's a bigger time commitment than simply pulling a lever on a voting machine since voters have to all caucus at the same time. A ranked choice system would make caucusing more accessible for rural and working class voters who can't feasibly carve out several hours of free time on a weeknight.

Cities like San Francisco and Santa Fe have implemented ranked choice for municipal elections, and New York City will be voting on whether to do the same this year. The only city to recently reject the change was Albuquerque, where the city council narrowly voted against it on Tuesday. But even there, one more initiative is still alive and should get a hearing before the end of the summer.