On December 4, New York Assemblymember Stacy Pheffer Amato was declared the winner of the 23rd district race, defeating her Republican opponent by fifteen votes. The race outcome had been in doubt until December 4. See this story.
Key to Pheffer Amato’s win was the discovery that about a dozen voters had cast a regular ballot for her, and had also written her name in. The vote-counting machines had rejected those votes because the machine could not possibly know that the voters had not voted for two different people (thus making their ballots invalid). Instead the voters had voted for her twice. Only human beings, not a machine, were capable of understanding these ballots.
This is similar to what happened in Florida in 2000, when about 7,000 voters voted for Al Gore the normal way and also wrote him in. About 3,000 voters did the same for George W. Bush. The machines rejected all those ballots because the machines thought the voters had voted for two different candidates for the same office, thus making their votes invalid.
No one knew about those Florida votes until November 2001, when a consortium of news organizations recounted all the Florida votes by hand and released the findings. Al Gore had never requested a recount of the overvotes (he only asked that the undervotes be counted).