According to the Los Angeles County Registrar-Recorder's Office, the issue was brought to officials' attention and poll workers are tracking the occurrences. The error stems from an apparent "random drop off" during the printing of the rosters, according to officials.
Several members of the Los Angeles County Board of Supervisors expressed their disappointment in a Wednesday meeting, where they questioned Los Angeles County Registrar-Recorder/County Clerk Dean C. Logan.
"This was an issue with the names being printed on the rosters of the polling places," Logan said. "This is not an issue where there is any question about the validity or the eligibility of these voters."
Gubernatorial candidate Antonio Villaraigosa asked the county Registrar as well as the Secretary of State's office to extend polling hours past 8 p.m. in light of the mixup.
"Obviously this is unprecedented, to have this number," Villaraigosa said Tuesday evening before eventually conceding the race to Gavin Newsom and John Cox. "We're hoping that it's just a mixup. But clearly I think I'm fairly calm about the fact that it's here in LA County primarily. That's anecdotally what we're hearing and this is the county I come from."
Initially, Villaraigosa was asking for the polls to be open later on election night. But his campaign later issued a statement asking for them to remain open until Friday.
Elections officials said to hold polls open past 8 p.m. would require a court order and no such order was filed in time, so the polls did close as scheduled.
A total of 1,530 voting locations were affected, and 118,522 voters' names were omitted from the lists, officials confirmed in a press release.
Officials urged registered voters who are told that their names do not appear on the list at their polling place to request a provisional ballot. "Those ballots will be processed and counted in the election returns," said Brenda Duran of the L.A. County Registrar-Recorder's Office.
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"We have adequate supplies at all locations to issue provisional ballots and again we want to stress that those ballots will be counted," Duran said.
Important Election Day Information: If your name does not appear on the roster at your polling place today, do not be alarmed. You will be given a provisional ballot and your vote will count ⬇️ #LAVotes pic.twitter.com/Ad6TBGryIx— Los Angeles County (@CountyofLA) June 5, 2018
Los Angeles County also tweeted out instructions to voters who might be experiencing the issue at their polling places. The county urged voters not to leave without casting their provisional ballot.
"Our office is committed to ensuring every voter has a positive voting experience on Election Day," Logan said. "We apologize for the inconvenience and concern this has caused. Voters should be assured their vote will be counted."
According to the registrar's office, an average of 85-90 percent of provisional ballots are deemed valid and are counted.
Watch the election results roll in live when the polls close starting at 8 p.m. here.