Ranked-choice voting (RCV) is having a good month. In what Larry Diamond, one of the nation's leading political scientists, says could be "looked back upon as the most important election in the United States in 2018," Maine's voters on June 12 reaffirmed their intention to allow for the ranking of candidates on ballots in state and federal elections (other than for president).

Maine's voters opted for ranked-choice voting once before, in November 2016. But a series of legal and legislative skirmishes by opponents including Maine's Republican Gov. Paul LePage landed the question on the ballot a second time. This time, RCV's winning margin doubled, growing from 4 to 8 percentage points.

In the same election, Maine's voters used the vote-by-ranking method to choose nominees in a multicandidate primary election. The tabulation took longer than expected — something RCV old hands in Minneapolis and St. Paul can understand. But turnout was unusually high, and voters told exit pollers that they liked being able to rank candidates in order of preference. They liked knowing that if their first-choice candidate fares poorly, their vote will help their second- or third-choice candidate, not (as often happens now when voters opt for a third-party candidate) the candidate they like least.

And RCV gives Maine voters the assurance that they won't again elect a governor who can muster only 38 percent of the vote, as they did when LePage was elected in 2010.

RCV was also used in the June 5 mayoral election in San Francisco to elect that city's first African-American female mayor. A June 9 editorial in the New York Times endorsed RCV as "a worthwhile experiment." Times columnist David Brooks had added his praise on June 1, arguing in a column headlined "One reform to save America" that RCV could be the thing that reverses the drift toward extremism in the nation's two big political parties.

In Minnesota, reports Jeanne Massey of FairVote, people have been calling to ask whether RCV could be used in the spate of multicandidate DFL primaries that suddenly appeared on the Aug. 14 primary ballot on June 5, the last day of the candidacy filing period.

Massey tells them that, alas, the answer is no. The voting method employed in primary elections is determined by state law, not political party policy. Ranked-choice voting is the law in city elections in Minneapolis, St. Paul and, as of 2019, St. Louis Park. To date, it has gone no further.

But the multicandidate DFL primaries for governor, attorney general, U.S. representative in the Fifth and Eighth districts, and several legislative races are primed to show Minnesotans why RCV is desirable at the state level. Each of those nomination contests this year could be won by candidates who garner less than 50 percent of the vote — in some cases, far less. The winners may or may not be the candidates who are most acceptable to the largest share of the party's voters. If winners with narrow appeal emerge, the party and potentially the state will be ill-served.

Until now, Minnesota's RCV advocates have sought to demonstrate its advantages one city at a time. They've been active in home-rule cities that can change their charters without the Legislature's permission, and they've asked the Legislature — without success — to give statutory cities the option to use RCV and a framework to guide them as they do.

That has been a worthy strategy for what has amounted to a series of demonstration projects. But when a consensus forms that plurality rule isn't good enough for Minnesota's democracy, more local demonstrations won't be a sufficient response to the people's demand for change. A month of news like this one should tell state lawmakers to expect more citizen calls for ranked-choice voting.