Election officials across California begin sending out mail ballots Monday, kicking into high gear the Nov. 4 contests for state, congressional and some local offices.
Registered voters have until Oct. 28 to request a mail ballot through their county registrar's office.
Voting by mail has become increasingly popular as laws changed over the years to allow anyone who is registered to request such a ballot and even to be put on a list to always receive a mail ballot without having to ask each time there is an election.
The ranks of permanent mail voters have grown dramatically, from 19% of those registered in California in 2002 to nearly half of the registration roll today, said Paul Mitchell of Political Data, which tracks election statistics.
Some groups are encouraging voters to sign up for mail ballots regularly in hopes of improving participation, especially among those who don't often make it to the polls.
In 2011, the state Democratic Party conducted a program in Los Angeles County in which it persuaded more than 50,000 Democrats who voted only occasionally to switch to permanent vote-by-mail status.
The new mail voters turned out at a significantly higher rate in the 2012 elections than that of county Democrats who went to polling places, state party spokesman Tenoch Flores said.
The trend toward mail voting means political campaigns must reach voters earlier. Television ads and political mail in some of the hottest races are hitting airwaves and mailboxes now to get the attention of early mail voters.
Previously, most so-called voter contact activities didn't occur until a couple of weeks before election day, when it was believed most people started to focus on the races.
But Mitchell said about half of those with mail ballots wait until the last 10 days or so to mark and return them, and many of those drop their ballots off at polling places on election day.
He attributes that to voters "liking the convenience of being able to take your time voting, but also sharing in that communal experience of going to the polling place and still getting your sticker."
The last day to register to vote in this election is Oct. 20.
Registration can be done online through the secretary of state at http://registertovote.ca.gov/ or through the counties, which also offer online registration. Residents must provide a California driver's license or state identification card number, the last four digits of their Social Security number and their date of birth.
Registration can be done in person at county election offices, Department of Motor Vehicles offices and many U.S. post offices, public libraries and some other governmental sites.
To get a paper application by mail, call a county office or the secretary of state's toll-free voter hotline, (800) 345-VOTE.