New Jersey county clerks and boards of election are struggling with thousands of ballots that have been deemed undeliverable for a number of reasons.

Monmouth County Clerk Christine Hanlon estimates there are 32 trays holding a total of 9,600 ballots representing people who very likely haven't received a ballot for the election.

“We open every one and see if there is any way to remail the ballot,” she says. “Some come back because the voter may be deceased. A lot come back because voters think the post office will forward their mail, but ballots are not forwarded.”

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Often, voters move out of town or out of state and do not update their registration. Out-of-staters, like college students, are proving difficult, because ballots can take two weeks to get to voters.

“So those voters we are sending priority mail to get them their ballots,” Hanlon says.

At $27 per ballot, this is proving to be expensive.

Another reason ballots are being returned is that the state mandated that ballots had to be mailed out by Oct. 5. But registration continued until Oct. 13, often leading to duplicates.

“So many people may have updated their address after the ballots went out,” Hanlon says.

Voters who have not yet received a mail-in ballot should call or email their county clerk’s office or go to the office in person. At the Freehold site, Monmouth County voters can fill out a ballot in person. Votes may also fill out a provisional ballot at their polling location on Election Day.

Hanlon says that this is just one example of the challenge that mail-in voting continues to place on county workers who often stay late into the evening to take care of ballot issues.

“One of the things we are concerned about is that we want to make sure every voter who wants to vote and is entitled receives a ballot,” she says.

Hanlon says that by next Tuesday, the county clerk’s office won’t be able to mail out ballots any longer because they won’t be able to guarantee that they will reach voters in time for the election.