SAN FRANCISCO (KPIX 5) — In California’s March primary, more than 100,000 mail-in ballots were rejected. For most of them, it was because they were not postmarked in time. That postmark date is critical. So now the country is facing a national election amid a pandemic, and voting by mail will be essential. What if the Postal Service can’t handle it?

“So we are very concerned, and we want the public to be aware,” says Mark Dimondstein, President of the American Postal Workers Union. “This is already starting to affect mail and packages.”

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The United Postal Workers Union is sounding the alarm over a budget crisis, increased delivery times, and a standoff with the White House.

“The Postal Service is a joke,” President Trump declared recently, rejecting the idea of a postal service bailout.

“The president is on record against vote-by-mail,” Dimondstein added.

So the worry is that a Postal Service in crisis will not be able to handle an election that will rely largely on the mail.

“If there’s not good access to vote by mail, tens of millions of people will be denied the right to vote,” Dimondstein warned.

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“California voters have a lot of experience with voting by mail,” explained Kim Alexander, President of the California Voter Foundation. “In the March primary over 70% of our voters cast vote by mail ballots”

Alexander says that should be reassuring news for Californians, but there is still confusion in the state, as evidenced by the 100,000 rejected ballots.

“You know, the confusing thing for some folks as we call this a vote-by-mail ballot, but that’s really about how it is arriving to you,” Alexander said. “It’s not necessarily how you have to return it.”

If voters want to avoid the worry of a ballot stuck in the mail, they can just avoid the risk altogether. Any ballot drop-off site will work, and no postmark is needed.

“If you’re going to send your ballot in through the mail,” said Alexander, “plan to send it at least one week in advance.”

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Other states with less experience voting by mail could face steeper learning curves. One recent survey found that in Virginia, 5% of ballots were rejected because they were not postmarked in time. That’s a significantly higher percentage than normally occurs in California.