SACRAMENTO, Calif. (AP) - Election Day in California could morph into election week because 50 percent or more of voters are expected to cast their ballots by mail and several statewide contests are toss-ups.

The number of voters requesting mail-in ballots has surpassed 2008, when 40 percent of voters cast ballots by mail.

The rise in mail-in voting means that some of the highest-profile contests, from a statewide tax initiative to nationally watched congressional races, might not be decided by the time voters go to bed Tuesday night.

Absentee ballots take longer to count because election workers must compare the signature on the mailed envelope with the one on that voter's registration card.

Elections officials are urging patience, and candidates say they are bracing for a tense few days after Nov. 6.

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