Sequoia Voting Systems, one of the top four voting machine vendors in the country, failed to print and deliver more than 18,000 absentee ballots to Denver County, Colorado, even though the company had assured officials the ballots were delivered, according to the Denver Post.

California-based Sequoia has a $742,000 contract with the county to print the ballots. Sequoia had told officials it sent some 21,000 ballots to a Denver postal facility on October 16, but postal officials said only about half that number arrived.

Officials learned ony over the weekend of October 25nd that Sequoia had failed to print and send the remaining ballots after voters started calling the election office complaining that their ballots hadn't arrived in the mail. Sequoia insisted that all of the ballots had been sent until election officials pressed the company to check its records. The company finally acknowledged that some 11,000 ballots had not been shipped as stated. Shortly thereafter, the number of missing ballots rose to 18,000. Sequoia sent the missing ballots last week, and Denver County voters have been told that they're allowed to turn in their mail-in ballots in person at any polling location on Election Day.

At least one Colorado voter contacted Threat Level and said he'd been disenfranchised by the screw-up.

He said he'd requested an absentee ballot two months ago because he travels often for work. When nothing arrived after a month, he contacted officials, who told him they had no record of his request. So he submitted a second request. When the ballot still didn't arrive, he contacted the elections office but was told to be patient and wait another week. The ballot finally arrived to his address on the 29th, but he's now out of state on business and can't get to the ballot to complete it in time before the election.

More than 193,000 mail-in ballots have been requested by Denver County voters, the Post reports. By Tuesday of last week officials had received only 66,044.

[REMINDER TO VOTERS: If you have problems casting a ballot, please contact us at vote@wired.com or add a report about your issue to our election map so we can track and investigate problems that come up. If you're adding a report to the map, please provide as much detail as you can to make it possible for us to verify the information. If you can provide us with your name and contact information to follow up with you and get more details, that would be even better. If you don't feel comfortable putting your name on the map, contact us at vote@wired.com.]

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