Coronado voters have until Monday, Oct. 19, to register and receive a mail ballot in time for the Nov. 3 election.

The deadline is three days away.

Voters who miss it can still register conditionally and cast a provisional ballot, but must do so in person at the San Diego County Registrar of Voters office in Kearny Mesa or at a vote center, according to the registrar's election information page.

Meanwhile, County Registrar of Voters Shawn Brom is warning all San Diego County voters not to drop mail ballots in a U.S. Postal Service (USPS) mailbox on Election Day. A ballot mailed that way may not receive a same-day postmark, as first reported by CBS 8 on Oct. 15. California law requires mail ballots to be postmarked on or before Nov. 3 and to arrive at the registrar's office within seven days.

"The postmark is key in order for us to actually count that ballot as being received timely," Brom said.

Brom said changes in how the USPS centralizes mail and applies postmarks are driving the concern. The USPS says it has not changed its postmarking practices but has adjusted transportation operations. That means some mail does not reach a processing facility the day it is mailed. Postmarks are applied by machine and reflect the date of first automated processing, not the date a letter was dropped off.

Voters who must mail a ballot on Election Day should take it to a post office counter and request a free manual postmark, according to both the USPS and Brom.

Drop boxes and vote centers

Brom's office recommends returning ballots through one of more than 150 official drop boxes open across San Diego County. Ballots are picked up daily. Drop boxes remain open through 8 p.m. on Nov. 3.

Select vote centers open Saturday, Oct. 24, from 8 a.m. to 5 p.m. daily. All vote centers open Saturday, Oct. 31. On Election Day, all vote centers, drop boxes and the registrar's office operate from 7 a.m. to 8 p.m.

Ballot returns running ahead

Brom said his office has mailed more than 2 million ballots countywide. As of Wednesday, Oct. 14, about 124,000, roughly 6%, had been returned. Brom said that pace is higher than in the June primary and the last gubernatorial general election.

Voters can track their ballot at sdvote.com and will receive an email or text when it is sent and again when the registrar's office receives it. The Nov. 3 ballot includes the governor's race, 14 state propositions, two countywide measures and additional local races and measures depending on where voters live.