The ballot includes a long slate of statewide and local candidates and ballot measures, including party nominations for president and an open U.S. Senate contest to determine the top two finishers who will advance to the November election.

In California, county election offices were required to begin mailing ballots to all registered voters no later than Feb. 5. Vote centers, which open 10 days before the election, are one of several options for voters to return mail in ballots or vote in person through Super Tuesday.

Voters can also submit completed ballots through the mail or return ballots at local vote-by-mail drop boxes.

People who want to vote, but missed the voter registration deadline, can fill out a conditional voter registration form at a vote center in order to cast a ballot, which will be tallied after election officials confirm voter eligibility.

The Los Angeles County Registrar-Recorder/County Clerk said vote centers will open daily from 10 a.m. to 7 p.m. through March 4. Voting centers and polling places will open earlier on election day, with polls closing across the state at 8 p.m.

At the urging of then Secretary of State Alex Padilla, who now represents California in the U.S. Senate, state lawmakers expanded voting access under a law approved in 2016 called the California Voter’s Choice Act. The law permitted counties to mail ballots to all registered voters and required vote centers to open 10 days before an election.

The changes were made in response to historically low voter turnout in 2014 and part of an effort to make it easier for Californians to participate in elections.

As of Thursday, 22.3 million registered voters received ballots in the mail and more than 1.4 million have been returned, according to the California Secretary of State’s office. The vast majority of the returned ballots, nearly 1.2 million, were submitted by mail.