NEW YORK (Reuters) - The Democratic primary race for Queens district attorney finally came to end an end on Tuesday with political newcomer Tiffany Cabán, a progressive backed by U.S. Representative Alexandria Ocasio-Cortez, conceding victory to Melinda Katz, the establishment favorite candidate.

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Cabán, a queer Latino, declared victory on election night in June, but since then, the two candidates had been battling over absentee ballots in a weeks-long recount ending in Katz’s favor. Last week, the New York City Board of Elections certified that Cabán lost by several dozen votes, but until now, the 31-year-old had yet to concede victory.

“We terrified the Democratic establishment,” Cabán said on Twitter. “There is still so much work to be done here in Queens — and you better believe I’m going to keep fighting.”

Despite Cabán’s loss, the close-run race by the 31-year-old marked a fresh signal of the growing power of the progressive wing of the Democratic Party as it pushes a populist platform across the country in the run up to the 2020 presidential election.

It also highlighted the political appeal that Ocasio-Cortez, known by her initials, AOC, has cultivated since she upset a long-time incumbent Democrat in a primary race a year ago.

Ocasio-Cortez did not immediately respond for comment.

Cabán ran a grassroots campaign, raising funds from small cash contributions.

She promised to close New York’s Rikers Island jail without replacing it, to decriminalize prostitution and to end cash bail for all criminal offenses.

Her progressive agenda gained her several high-profile endorsements, on top of Ocasio-Cortez’s. Bernie Sanders and Elizabeth Warren, both leading progressives in the U.S. Senate and candidates for the Democratic nomination for president both backed her.

Katz’s 25 years as a public servant representing the Queens district — first as a member of the State Assembly, the City Council and then as borough president — had been reduced during the campaign for her political ties to establishment candidates, including Governor Andrew Cuomo, and local businesses.

Katz thanked Cabán on Tuesday and acknowledged the reassured voters that she and Cabán are more alike than not.

“Too often, the process of primary campaigns obscures the vast commonalities we share as Democrats and reformers,” Katz said in a statement. “We all want a safe Queens where everyone is treated equally.”