On September 4, 2024, Democrats across Washington State let out a collective sigh of relief. A recount of the primary election finally confirmed that one of their own, then-King County Councilor Dave Upthegrove, would appear on the November ballot. Even though Democrats had won 270,000 more votes than Republicans in the primary for Commissioner of Public Lands, Upthegrove squeaked into second place by just 49 votes.

This math story problem gone awry is a hiccup of Washington's top-two primaries, in which the two candidates with the most votes, regardless of party, square off in the general election. Democratic voters split their majority five ways, allowing two Republicans to float toward the top of the pool with a combined 43 percent of the vote. Only the narrowest of margins spared blue-leaning Washington an all-Republican ticket in the general election. (It wouldn't have been the first time.)

So do Washington's nonpartisan top-two primaries need to go? Certainly not. Two decades of research point to their overall positive impact on elections and governance. Compared with the 47 states that use partisan primaries, the top-two model has a depolarizing effect on lawmakers, gives candidates an incentive to appeal to wider audiences, and turns out a more representative electorate.

But while Washingtonians could claim for years to be leading the pack on primary reform, the top-two model has also stumbled, occasionally producing backward results and unfavorable conditions for third parties. Since 2020, Alaska's top-four primaries and ranked choice general elections have avoided top-two's tripping points while still retaining and building on its positive qualities.

Washington's not down and out by any means; with a simple top-four (or top-five) tune-up, Evergreen state voters could get the same results.

In 2004, Washington voters approved Initiative 872, which created top-two unified (or nonpartisan) primaries. In these races, all candidates appear on the ballot together and the top two vote-getters (of any party) advance to the general election. California adopted the model six years later.

Most states hold partisan primaries, which are exclusive to candidates of a given major party and tend to produce combative campaigns and extreme legislators. But reformers theorized that unifying the races - i.e., making them nonpartisan and allowing all voters to participate - would produce more moderate legislators who better represented the majority of voters.

They were right. Political polarization stabilized in the California and Washington legislatures post-reform while the problem worsened in most states with partisan primaries.

Why such a dramatic difference? For one thing, unified primaries tend to turn out more voters that better represent the overall electorate than partisan primaries, which skew older, whiter, wealthier, and, some researchers suggest, more ideologically extreme than those who show up for general elections. Because Washington's unified primary voters look more like the general voting public than most other states, candidates and lawmakers have cause to court voters from all sides (not just a narrow base) to secure one of the top two spots.

Another key element is that the top two candidates regardless of party advance out of the primary. Two Democrats or two Republicans can face off in the general election if an area skews heavily toward either party. Voters of the dominant party get more options in the general election, while voters in the political minority can sometimes "play kingmaker," putting a more moderate candidate over the top.

There's no better illustration of the dynamics top-two has introduced than Washington's Fourth Congressional District. About 60 percent of voters in the district backed Donald Trump in 2016, 2020, and 2024. But Rep. Dan Newhouse, one of only two US House Republicans to vote to impeach Donald Trump and win reelection in 2022, has won out over a more conservative fellow Republican i...