Through a 2020 ballot measure, Alaskan voters enacted a top-four primary. In this system, candidates list themselves on the ballot in three possible ways: as affiliated with a political party or political group, as undeclared or as nonpartisan. The four candidates who get the most votes move on to the general election, in which ranked-choice voting is used to determine the winner. (In ranked-choice voting, rather than selecting just one candidate, voters can instead choose several and rank them.)

This reform aims to increase the likelihood that candidates with the broadest appeal to voters, rather than more factional candidates, will win the election. In a traditional primary, in which many candidates can split the vote, factional candidates can prevail by drawing, say, just 25 percent of the vote. Because factional candidates often hold more extreme views, this reality helps fuel dysfunction in American politics.

In a recent book, “Rejecting Compromise: Legislators’ Fear of Primary Voters,” a group of political scientists found that “legislators believe that primary voters are much more likely to punish them for compromising than general election voters or donors.” Incumbents in safe seats often embrace more extreme positions to avoid facing challengers in primaries. And some moderate incumbents who might have broad appeal in a general election are now retiring rather than competing in primaries they are likely to lose to ideological extremists.