To the dismay of Democratic Party leaders and delight of their Republican Party counterparts, early polls raised the possibility of two Republicans running for governor in deep Blue California this fall. Coincidentally, as the state mailed the June 2 primary ballot to registered voters, a Democratic political consultant proposed a ballot measure titled “Undo the Top-Two” to ask voters to abandon the “open” primary. The nation is watching and voters are wondering as this drama unfolds.

How did California come to have a top-two primary system, what outcomes has it produced, and why is the political context in which it is operating in the 2026 election cycle so important to its future?

In June 2010, Proposition 14—titled “Primary Election Participation”—asked California voters to replace a political party ballot with an open ballot that would allow all California voters to vote for any candidate for a statewide elective office (such as governor), the state legislature, or Congress. The two candidates who receive the most votes in the primary would then move on to the November ballot. (The state would continue to have partisan primaries for presidential races.)

Proposition 14 supporters, led by Governor Arnold Schwarzenegger, claimed that all voters would be able to choose any candidate regardless of their party affiliations, and independent voters would gain a greater voice in selecting primary candidates. Proposition 14 opponents, including the major and minor parties, claimed that open primaries would reduce the number of candidates in general elections and may result in two candidates from the same party on the general election ballot (sound familiar?).

A majority (54%) voted yes in June 2010, and Proposition 14 went into effect for the 2012 election.

After more than a decade in use, the top-two approach has encouraged some voters to vote differently—but most have been “staying in their party lanes,” and incumbent candidates continue to do very well. The open primary also seems to have promoted at least a little more moderation among winning candidates. The evidence for voter turnout is mixed and complicated by efforts to increase voter participation, including all-mail ballots starting in 2020.

The top two has led to same-party races—at least 18 for state legislature or Congress in every fall election under the reform. In most cases, the partisan outcome would have been the same without the top-two approach. These include races with two candidates from the dominant party in a safe district, as well as a few races in potentially competitive districts where only candidates from one major party ran in the primary. Nonetheless, in eight November races, two candidates from the same party ran in a competitive district or a district that actually favored the other side. All but one of those races featured two Republicans.

The same possibility at the state level has animated discussion about the top two this election season. Two closely matched Republican candidates and a large field of qualified Democratic candidates without a frontrunner has resulted in pre-election polls with no clear leaders for the top-two spots. While some fall statewide races have featured two Democrats—most notably the 2016 and 2018 US Senate contests—no statewide race has ever featured two Republicans.

Democrats still have a good chance of placing first or second (or both) in the primary. Two Republicans on the November ballot is a long shot given the state’s voter registration (45% Democrats, 25% Republicans, 23% no party preference, 7% other) and partisans’ unwillingness to choose candidates from outside their party.

After the 2012 election cycle, 59% of likely voters said that Proposition 14 turned out to be “mostly a good thing” for California, with similar responses in 2017 (60%), 2022 (62%), and 2024 (68%). In our most recent polling, majorities across political groups and along the political spectrum agreed.

As Californians ponder their ballot choices for the June primary, it is noteworthy that 46% of likely voters choose “threats to democracy and political extremism” when asked to name the most important problem facing the US today. In this context, most Californians want to feel assured that candidate choices will reflect their partisan leanings in the November general election. And political anxiety is running high about the outcomes of the 2026 midterm elections.

All the same, major factors will limit the voters’ desire to “undo the top-two” and welcome back the partisan primaries. Most importantly, majorities of likely voters have unfavorable views of the Democratic Party (61%) and the Republican Party (70%). In fact, unfavorable ratings have increased significantly since 2012. Just one in four think that the Republican and Democratic parties do an adequate job of representing the American people, and three in four think both parties do such a poor job that a third major party is needed.

Voters might consider undoing the top two if this would provide an opening for a third major party on the November ballot. But a campaign that emphasizes the value of the two major parties may fall on deaf ears.

We will continue to track attitudes toward the top-two primary as this election cycle unfolds.

Presidential election results by district were scraped from the Secretary of State’s website and formatted using ChatGPT Codex; for validation, results were plotted against partisan outcomes and vote numbers were spot-checked for key same-party races.