Melinda Katz was declared the official winner by the New York City Board of Elections.
She beat Tiffany Caban by just 60 votes, following a a two-week-long manual recount of more than 90,000 votes.
But Caban's campaign has filed a legal challenge over more than 100 ballots that were invalidated. Those ballots remain unopened.
Cabán and her team say if those ballots are opened and counted, they could tip the vote back to her.
"Our campaign is fighting to protect Queens voters from being disenfranchised and allow their voices to be heard," Caban campaign spokeswoman Monica Klein said.
Katz released the following statement:
"While it is everyone's right to avail themselves of the judicial process, I urge all participants in this hard-fought election to come together and join me in beginning the hard work of reforming the criminal justice system in Queens. This is a major moment for this borough, and it will take the support of all its residents to make this effort a success. I will be spending the months ahead preparing for this critical task."
The primary winner is expected to win the general election in November.
Watch the Board meeting below:
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