Washington (CNN) Tiffany Cabán has conceded the race for the Democratic nomination to be the next district attorney of Queens County, New York, after the race was too close to call following the June election.

Cabán, a young, progressive outsider, ran against Queens Borough President Melinda Katz, who had the backing of most traditional local power brokers, and several other candidates. The results of a manual canvass left Katz with a narrow win.

Cabán preached a message of hope in her concession speech on Tuesday night.

"So this election may be over, but the organizing does not stop. It will not stop," the candidate said at a party for supporters and volunteers. "I look forward to continuing the fight alongside y'all, and we are just getting started."

The attorney, who is of Puerto Rican descent and identifies as queer, had hinged her campaign on a promise to effectively decriminalize a series of low-level offenses that law enforcement and prosecutors began cracking down on during the "tough on crime" era of the early 1990s. That means refusing to prosecute subway fare beaters, recreational drug-related crimes, resisting-arrest charges -- especially when they are not attached to more serious allegations -- loitering and other offenses, like sex work. Cabán also had pledged to wipe out cash bail, and her long-term goal was to achieve "population zero" in the city's prisons.

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