While this may sound alarming, the county's Registrar of Voters (ROV) office told ABC7 News it is common. Election officials assure no vote is counted twice.
Essentially, 50 days before the election, ballot printers receive voter files and the system sends out ballots. The county's system then generates a second ballot to reflect any changes made by a resident within those 50 days.
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"Anything at the post office, anything at DMV, anything at the Secretary of State website," public and legislative affairs manager for the county's ROV, Evelyn Mendez said. "Any forms that they bring here, changing their signature, their phone number, anything will trigger off another ballot."
Mendez said similarly, people can request a second ballot in case the first is lost or misplaced.
"We have systems in place to make sure that only one of those ballots is counted. So whatever ballot gets received back to our office is going to be the ballot that we count," she described.
By Tuesday afternoon, Mendez said 14% of ballots had been returned. She said the hope is 55-65% turnout.
She said this weekend, all 103 of the county's vote centers will be open to assist voters with questions and concerns.
Elsewhere, there was a final effort to reach more people across the county-specifically, voters of color.
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ABC7 News visited Westminster Presbyterian Church in San Jose for the final Tuesday night "Together We Vote" phone banking session.
Organizations including the Latina Coalition of Silicon Valley, Black Leadership Kitchen Cabinet and People Acting in Community Together have worked in partnership since the summertime to host such sessions.
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Executive Director of the Latina Coalition Gabriela Chavez-Lopez emphasized the importance of the collaborative effort, pointing to the population being disproportionally impacted during the pandemic as the driving force.
"We wanted to make sure that as we're thinking about the future and those that represent us, that they have our needs and desires and wants in mind when we think about an equitable recovery," Chavez-Lopez explained.
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The final phone bank was held on Dia de los Muertos, which Chavez-Lopez said was significant timing, "This is one way in which we can honor those that have come before us-to fight for that right, as well as those that have come after us-our children and our future generations. So that's something we're encouraging many people to think about as they're going to the ballot box."
She said during the primaries, "Statewide, our voter turnout was about 15%."
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So, where there's concern about whether multiple ballots mean people might vote twice, there's a greater effort to get people to vote just once.
"We wanted to get ahead of it, we wanted to make sure that we weren't just lamenting that not enough of us turned out," Chavez-Lopez told ABC7 News. "We wanted to make sure that we put in the work-that we reached out to our communities, that we made the calls."