Contra Costa County officials may have as many as 60,000 late ballots that still need to be counted in Tuesday night's election.
County Clerk Steve Weir based that prediction on the fact that about 20 percent of vote-by-mail ballots are turned in at the polls on Election Day.
That, combined with the ballots that arrived on Saturday and Monday plus 12,000 to 15,000 provisional ballots, make for a lot of work left for election officials.
Weir said he'll know by 5 p.m. Thursday exactly how many ballots are left uncounted. He said they might not all be counted until sometime next week.
That could leave several elections in doubt until then.
One of them is Measure D, the $260 million school bond in the San Ramon Valley. Right now, the measure has 55.19 percent of the vote with 55 percent needed for passage.
It's not known how many uncounted ballots are from Alamo, Danville and San Ramon.
The voter turnout right now for Contra Costa County is 60 percent. The late ballots are expected to raise that to 80 percent.
The county has until Dec. 4 under state law to certify the election.