The wait reflects two factors working together—how quickly ballots are processed and how narrow the race is. Election-night winners announced by news organizations are projections based on partial results, not confirmation that every ballot has been counted. In a landslide, early returns may be enough to identify a likely winner. In a tight race, analysts need more votes counted before making that call.

“Margins matter,” said Stephen Richer, a Republican who previously served as clerk and recorder in Arizona’s Maricopa County. He said places with lopsided contests can appear to finish quickly even though ballots remain to be counted.

California faces both close races and a comparatively slow count. The state has many competitive congressional districts, though fewer than in some recent elections: the Cook Political Report rates three California House races as competitive this year, compared with nine ahead of the 2022 midterms. Voters approved a mid-cycle redistricting plan in response to Republican-led redistricting in other states.

A major source of delay is the large number of mail ballots returned on Election Day. Those ballots require processing, including envelope handling and signature checks. Kim Alexander, who leads the California Voter Foundation, said some counties receive as many as half their mail ballots on Election Day, leaving that work to begin later.

California has set aside $40 million to speed ballot counting this year, including money for voter education. Alexander said voters can help by returning ballots earlier or using other voting options that allow ballots to be counted sooner. Research in San Joaquin County found that postcards encouraging voters to cast ballots earlier made them more likely to meet a recommended deadline for election-night counting.

The state’s slow count has also made it a focus of false claims about election administration. MIT elections expert Charles Stewart described California as having “a big target on its back.” Richer said California’s mail voting policies and political profile contribute to what he called an “incendiary situation.”

Alaska could be another state to watch. It was the last state to reach 95% of ballots counted in 2024, according to MIT Election Lab data. The Associated Press did not call Alaska’s single House race that year until Nov. 20, more than two weeks after Election Day; Republican Nicholas Begich won by fewer than 10,000 votes.

This year, polling indicates a close Alaska Senate race. If the contest is close and its outcome determines control of the Senate, the balance of power could remain uncertain for weeks. The extended count does not, by itself, indicate a problem with the vote; it can reflect the time needed to process ballots and establish a reliable result in a narrow contest.