But the fight isn't over.
After a two-week-long manual recount of more than 90,000 ballots, Katz came out 60 votes ahead of public defender Tiffany Cabán.
"The board has worked tirelessly to ensure that every vote is counted accurately and correctly," Board of Elections President John Zaccone said.
But Cabán is challenging the recount in court, because 114 paper affidavit ballots were tossed out as invalid.
Those ballots remain unopened.
Cabán and her team say if those ballots opened and counted, they could tip the vote back to her.
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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