The registrar's office is trying to make it as easy as possible for individuals to register.
"It's a very simple process. Again, the fastest way is to do it online. If you have a California driver's license or I.D. card, it'll link to that information, get your signature from there and you can complete that in, literally, a couple of minutes," said Los Angeles County Registrar-Recorder/County Clerk Dean Logan.
You can also mail your form if it's in the mail by Monday.
Registrar offices in L.A., Orange and Ventura counties, as well as the Inland Empire are open for people to drop off their registration applications. Many offices will be open until midnight for such drop-offs.
About 75 percent of of all eligible voters in the state are already registered to vote, according to Sept. 7 report from the office of California Secretary of State Alex Padilla.
To register online or to check if you're already registered, click here.
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"It definitely matters," said L.A. County CIO Aman Bhullar. "Every vote matters, and we want to make sure that people out there go out and vote so that their voice can be heard."
The deadline to register to vote in person is Tuesday, Nov. 6 - which is Election Day. Californians who miss the Monday registration deadline will have all the way up to Election Day to register, thanks to the conditional voter registration process.
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If you can't make it to your polling place on Nov. 6, L.A. County will have 10 locations open two weekends before Election Day. Those weekends are Oct. 27 and 28 and Nov. 3 and 4. Visit this Weekend Early Voting site for information on early voting centers.
In L.A. County, there are 6.1 million people who are eligible to vote, but only 5.2 million have actually registered, according to the registrar recorder.
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So why have 1 million people not registered, especially millennials? Logan said it's not so much apathy, it's more about making the connection between voting and being meaningful to other things that they're already doing in civic life.
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Get the latest updates on elections news at: abc7.com/vote.
For everything you need to know about all the California propositions, check out our 2018 Voter Guide.