SCARBOROUGH — Missing ballots discovered from Tuesday’s school budget vote narrowed the margin, but didn’t change the referendum outcome.

The budget passed by a margin of 176 votes, town officials said Wednesday, 2,402 to 2,226.

Officials Wednesday discovered 420 uncounted ballots from Tuesday’s school budget referendum vote, which initially passed by 238 votes.

Election workers convened at 10 a.m. to count the missing ballots and update the tally, according to a town press release.

The vote Tuesday evening was 2,223 to 1,985 in favor of the proposed $47.1 million school budget.

“A discrepancy was identified between the total number of votes reported at 4,208 and the total number of ballots printed,” the press release said. “It was quickly identified that a box of absentee ballots, totaling 420, was left in the vault and not counted in the final tally.”

The statement said final results will be validated by the Town Council at it meeting Wednesday night.

“The integrity of the election process and confidence in our abilities to conduct fair and open elections is paramount,” the statement said. “We apologize for any inconvenience this may cause and we appreciate your patience as we work to produce final and complete election results.”

Tuesday’s vote was the third attempt to pass a fiscal 2018 school budget, and the second time uncounted ballots were discovered.

On Aug. 30, the town announced 200 uncounted ballots from the July 25 referendum were discovered by Town Clerk Tody Justice on Aug. 21. The uncounted ballots were evenly split, 100-100, and did not change the outcome.

Last November, Justice initially failed to count more than 2,700 absentee ballots that were stored on a thumb drive. That mistake required a recount in the general election that took almost nine hours.