California

California, the nation's most populous state, runs its elections almost entirely by mail, with every active registered voter sent a ballot and the large majority returning that ballot rather than voting in person—about nine in ten in the June 2026 primary, and 81% in the 2024 general election. The state counts more ballots, and counts them more slowly, than almost every other state, a pattern that has drawn national attention. In this report, we discuss the state's 2026 electoral landscape and provide analysis of its primary elections. 

California provides statewide and county-level data on election results, voter registration, turnout, and voting equipment. In this document, we identify the locations of the data and their dedicated webpages, and detail the variables provided by the state and by Los Angeles, San Diego, Orange, and Santa Clara counties.

California held special elections on May 12, 2020, featuring races in two Southern California jurisdictions: a race for the 25th federal congressional district, and a race for the California state Senate’s 28th District. Due to the ongoing coronavirus pandemic, special procedures were implemented--every registered voter  received a ballot through the mail, and most in-person voting was suspended. There were no in-person voting options for Riverside County, only 10 options in Los Angeles County, and 3 in-person options in Ventura County. Despite these challenges, turnout rates for both the Congressional seat and the State Senate seat were within the normal range for a special election in California--a significant accomplishment, given the difficult circumstances. 

These elections are not a perfect model for understanding California’s preparedness for the 2020 Presidential election because in-person voting options were more restricted than they will be in November.  Nevertheless, these elections show California’s legacy of extensive voting by mail is paying dividends, and Governor Newsom’s Executive Order requiring all county elections officials to mail ballots to all registered voters puts California on firm ground going into the presidential election.

Transferring the lessons of these special elections to other states may also be an issue, especially for states that do not have the existing vote-by-mail infrastructure that California has. However, close to 1,000,000 ballots were mailed out across the 2 special elections, which means more ballots were needed in this special election cycle than there are voters in 15 states.