California’s primaries are the most unpredictable in America

LOTS of things come with warnings in California. Signs in parking garages admonish drivers that they could be exposed to carbon monoxide gas. Recently a judge ruled that coffee-sellers must warn of cancer. Voting instructions also come with an alert. Under a bold exclamation mark, a mail-in ballot insert sent to Los Angeles voters in anticipation of California’s primary elections on June 5th reads: “There are 27 candidates for governor” and “There are 32 candidates for US senator”, adding: “If you vote for more than one candidate, your vote will not count for that contest.”

In many states, primary elections are simple affairs. Voters who are registered with a party pick a champion from their side to contest the general election. But in 2010 Californians approved a “top-two” primary system, in which all voters receive the same ballot and can choose anyone they like. The two most popular candidates move on to the general election.

Eight years ago California was notorious for its extremely left-wing Democrats, its extremely right-wing Republicans and its political paralysis. The few moderates, such as then-governor Arnold Schwarzenegger, championed primary reform as a way to empower centrists. In theory, top-two primaries encourage candidates to appeal to lots of voters, not just the ideological purists who turn up for ordinary primary elections. Constituency boundaries and term limits were altered at about the same time.

The results have been mixed. California’s legislature is more popular than it was (see chart). On the other hand, just 18.4% of eligible voters voted in the primaries of 2014, the first non-presidential election year since the reform was enacted, down from 24.1% in 2010. A study last year by Eric McGhee, a researcher at the Public Policy Institute of California, and Boris Shor, a political scientist at the University of Houston, examined the ideologies of candidates before and after top-two primaries were introduced in California and Washington state. Evidence of moderation in both states was “modest and somewhat inconsistent”, they decided.

One clear result of top-two primaries is that they have led to non-partisan general elections. That happened in 2016 when Barbara Boxer retired, leaving open her seat in the US Senate. Kamala Harris, a Democrat, went on to defeat Loretta Sanchez, a fellow Democrat. This year’s governor’s race may set Gavin Newsom, a Democrat and former mayor, against Antonio Villaraigosa (ditto).

The reform now threatens to produce weird results. When many Democratic or Republican candidates pile into a race (as Democrats in particular are doing this year) they threaten to split the party vote and allow two finalists from the other side. So parties put pressure on their own candidates to drop out. Sometimes they go for the other side. In the election to replace Ed Royce, a Republican congressman for California’s 39th District, Democrats have begun airing advertisements attacking relatively weak Republican candidates. They hope to ensure that the front-runner, Young Kim, is the only Republican to reach the general election. The Democratic Congressional Campaign Committee is using similar tactics in several other races across the state, where the stakes are high. They need to flip 23 seats in November’s midterms to reclaim control of the House of Representatives. Ten of the races deemed competitive by the Cook Political Report, a political newsletter, are in California—the most of any state.

“We tried to warn people that this was a bad idea,” laments Bruce Cain, a political scientist at Stanford University. “But all you have to do in California is wave the flag of reform and people say: ‘Yay! Good idea! Reform!’”