California’s primary elections, including a fiercely contested gubernatorial race, entered the final hours of voting Tuesday with election officials bracing for a slow-motion count that could leave the outcomes of the tightest contests unknown for days or weeks. Voting experts said the state’s 58 county elections offices expect to receive a deluge of last-minute absentee ballots, triggering a painstaking, ballot-by-ballot verification process that has delayed resolution of federal races in past cycles.

The procedural bottleneck is familiar to California voters and to a national audience that waited through the 2020, 2022, and 2024 election cycles for the state to finish counting its votes and determine control of the U.S. House of Representatives. In the 2024 presidential election, more than 25% of California’s vote total arrived too late to count by election day. The percentage could be even higher this time, experts said, because many voters strategically postponed casting ballots until they had a clearer picture of the crowded governor’s race.

That race, according to final polls, is a volatile three-way contest between two Democrats — former U.S. Attorney General Xavier Becerra and billionaire environmental activist Tom Steyer — and Republican frontrunner Steve Hilton, a former adviser to British Prime Minister David Cameron. A fourth candidate, Riverside County Sheriff Chad Bianco, has focused his campaign on unsubstantiated claims of election fraud and earlier this year attempted to seize 650,000 ballots in a search for evidence; a court blocked the effort.

Kim Alexander, president of the California Voter Foundation, a nonpartisan voting rights group, said the prolonged counting period erodes voter confidence across the political spectrum. “Like it or not, the more time that passes between election day and when results are known, the more voter confidence erodes,” Alexander said. She called the delay “an invitation to false claims about the reliability of the voting process even though we have the most accessible, secure and verifiable election system in the country.”

MSI previously reported on the risks the slow count creates for the state’s elections, as Newsom signed a law shielding the state’s elections from federal interference.

California’s vote-counting procedures are widely praised for their security. Poll workers must cross-check each absentee ballot envelope’s signature against voter registration records and verify that no individual cast more than one ballot. Voters who forget to sign envelopes or otherwise invalidate their ballots receive a time window to fix errors so their votes can still count. But the thoroughness slows the process. Alexander and other experts said many Californians are unaware that submitting an absentee ballot within three days of election day causes the deepest processing delays; in 26 counties, voters have the option to walk their absentee ballot into a polling station for on-the-spot processing, an alternative Alexander said should be promoted statewide.

Newsom sent a letter to county election offices last month urging them to accelerate their counts. “Time is of the essence in preventing election lies from taking hold,” Newsom wrote. “We face an assault on our democratic values unlike anything we have seen in our lifetimes, and it’s our job to safeguard those values.”

The state’s Republican party, which has not won statewide office in 20 years, has pointed to the slow count as evidence of broader malfeasance, despite the absence of evidence. Former President Donald Trump has been particularly critical of absentee ballots, which he has blamed for his 2020 defeat, and has repeatedly alleged that California’s results are padded by millions of illegal votes cast by noncitizens — a claim that election officials across the state have said is false. Hilton has embraced a November ballot initiative that would impose voter ID and proof-of-citizenship requirements; critics, pointing to states such as Indiana and Ohio that have adopted similar measures, said it would suppress turnout among lower-income and minority voters without addressing any documented problem.

California’s state legislature has responded by passing a series of new laws, most with unanimous bipartisan support, that tighten county reporting deadlines so all non-problem ballots must be counted within 13 days instead of the current 30-day window. The laws also limit the time voters have to correct signature errors and other mistakes. But the mandates came with no new funding. County election officials said they are expected to do more with the same limited resources. Secretary of State Shirley Weber, California’s chief elections officer, opposed one of the new bills, arguing that it placed unreasonable pressure on counties. Alexander said the state’s wealthier counties, including Los Angeles and Orange, have invested their own money in new facilities and achieved significant efficiency gains, proving that faster counts are possible. “One of the challenges we face is the misconception that we have to trade speed for accuracy, or access, or security,” Alexander said. “I believe that’s a false choice. We can have all of those things if we’re willing to pay for it and if we do the hard work to achieve it.”

Going deeper: Read MSI’s analysis of California primary ballot counting delays →