About 22 million vote-by-mail ballots were sent to registered voters in California for the Super Tuesday election.
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Although only a small fraction of them will be returned in the primary election, county elections offices will still need to count millions of ballots statewide -- a process that will likely take days to complete.
California mails every active registered voter in the state a vote-by-mail ballot, a practice that began during the COVID-19 pandemic. As of Sunday, more than 3 million vote-by-mail ballots had been returned. In Los Angeles County, the state's most populous county, that figure stood at about 519,700.
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More people will vote in-person on Tuesday when vote centers around the state are open from 7 a.m. until 8 p.m.
So what happens next?
County elections official must begin reporting results to the California Secretary of State no more than two hours after they start the vote tally when vote centers close. California's 58 counties continue to periodically report results to the state throughout election night.
The first results are usually ballots received before Election Day, whether they were mailed back or dropped off at a drop box or vote center. The process of opening and processing those ballots can begin up to 29 days before Election Day.
Those results can't be made public until polls close.
"All of the ballots that were received through this past weekend have already been opened and separated from the identity of the voter, examined and scanned through out tally system," Los Angeles County Registrar-Recorder/County Clerk Dean Logan said Tuesday. "Now, they haven't been counted, yet. They've been scanned in, and then at 8 o'clock when the polls close we can run that software program that's going to accumulate the totals off of those ballots. The first results we'll have, probably around 8:30 p.m., will represent the vote-by-mail ballots that have been cast prior to the election."
In-person votes cast over the previous 10 days are usually next, then day-of votes are counted throughout the night and beyond.
Any results posted on election night are considered semi-official, and a complete tally of votes won't be completed Tuesday. For one thing, mailed ballots postmarked on or before Election Day and received by the county within seven days after the election, plus provisional ballots, still need to be counted.
Based on semi-official results, candidates might "concede" to an opponent and news organizations might project a result on election night, but the official election results for many races likely won't be available for days. Results are never final until the Secretary of State compiles statewide results and all counties have reported an official canvass of the vote.
Counties have 30 days to complete that canvass. That means counting every valid ballot and conducting a post-election audit. During that 30-day period, elections officials compare signatures on ballot envelopes to signatures on file.
The Secretary of State is then required to certify results 38 days after the election.
