By CBSLA Staff

LOS ANGELES (CBSLA) – A sign of what could be incredibly high turnout, about 370,000 residents in Los Angeles County have already cast mail-in ballots so far, the L.A. County Registrar-Recorder reported Tuesday.

Voters cast their ballots at an official ballot drop box on a sidewalk in Los Angeles on Oct. 12, 2020. (Getty Images)

369,851 vote-by-mail ballots had been returned as of Monday night, according to the registrar’s office.

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L.A. County had 5.73 million registered voters as of Oct. 9, representing about one-quarter of the overall number of voters in the state, which sits at around 21 million. The deadline to register to vote is Monday, Oct. 19.

The three ways to vote in this year’s general election are by mail, in person or by using one of more than 400 official drop boxes installed countywide to return a vote-by-mail ballot.

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Local and state officials are currently investigating several unauthorized ballot drop boxes which have popped up across L.A., Ventura and Orange counties in recent days. The California Republican Party has admitted to installing some of them, arguing that doing so does not violate the law.

Some of the boxes are labeled as “official” drop boxes even though they are not.

People can be designated to drop off someone’s ballot, as long as that person is not on the voter’s payroll, by indicating that preference on their ballot envelope.

All registered voters in California have been issued mail-in ballots, which will be counted if postmarked by Nov. 3.

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(© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)