https://www.mercurynews.com/2020/01/27/california-primary-solano-county-ballots-vote-early-mail/

California’s 2020 primary unofficially kicked off last week as Solano County became the first county in the state to send voters mail-in ballots — giving residents the chance to cast some of the earliest presidential ballots in the U.S.

The 180,149 ballots were the first sent out anywhere in California other than those going to military or overseas voters, according to political observers, and mark the beginning of an election that is expected to see more votes cast through the mail than ever before.