Californians will continue voting when polls close on the East Coast and the first states begin reporting their results at 5 p.m. Pacific Time.

But officials have warned that it could be days before they know who won the presidency. With polls showing a historically close race, the closer the preliminary results are, the longer it will take to determine a decisive margin in the Electoral College, allowing the media to project a winner.

In 2020, it took four days for major media outlets, including the Associated Press, to make that call for President Joe Biden. The three swing states that took the longest in that election, Pennsylvania, Arizona and Nevada, could again be factors in a prolonged wait for a projection this year, a According to the Washington Post.

Determining which parties control the House and Senate may be easier on election night or shortly afterward.

There is also a mix of results at the state and local level, the first of which will be posted on the Secretary of State and county elections office websites shortly after 8 p.m.

John Tuteur, Napa County registrar of voters, said the first unofficial results for mail-in ballots received through Sunday will be released on election night at 8:01 p.m.

Then, before 10 p.m., the county plans to release its unofficial count of in-person ballots received during early voting from Oct. 7 and Election Day, Tuteur said. An additional unofficial release of in-person ballot results will be made before midnight on Election Day, Tuteur said.

Sonoma County Registrar of Voters Deva Marie Proto said results from in-person early voting ahead of Election Day and primary ballots received over the weekend (and possibly Monday) will be released immediately after that voting ends at 8 pm on Tuesday.

Periodic updates will follow, depending on how quickly ballots are processed after polls close, he said.

“We will have updates; we don’t know when, it depends on when the ballots arrive at our office from the voting centers,” Proto told The Press Democrat on Friday. “We will continue to update until we have received all ballots from the voting centers.”