Millions of Californians have not yet returned their vote-by-mail ballots, and the flood of returns expected on election day could delay results in tight races, officials said Monday.
The state's 58 counties had reported receiving just under 3 million absentee ballots as of early afternoon Monday -- less than 40 percent of the 7.6 million ballots requested statewide for the general election, according to the California Association of Clerks and Election Officials.
In some counties, vote-by-mail is expected to exceed in-person voting.
That means a huge number of last-minute returns will not be processed Tuesday, and the most competitive races may remain too close to call.
"The ballots are coming in later than average and there's more of them than average, which means more uncounted ballots on election night," said Contra Costa County Clerk Steve Weir, who estimated that one-quarter of his county's absentee ballots would not be included in Tuesday's tally.
Recent polls show a number of extremely close contests in California, including the races for lieutenant governor and attorney general. In addition, about half a dozen congressional seats and several state legislative seats are thought to be in play.