State Sen. Tony Avella defeated former New York City Comptroller John Liu in the Democratic primary for the state’s 11th Senate District.

According to unofficial returns, with almost all precincts reporting, Avella had 52 percent of the vote, to Liu’s 48 percent. The district covers parts of northeast Queens.

Avella, a former member of the New York City Council, was first elected to the state Senate in 2010. He’s a member of the Independent Democratic Caucus, a group of breakaway Democrats helmed by state Sen. Jeff Klein, which shares control of the Senate with Republicans.

The group splintered from fellow Democrats, and the power-sharing arrangement allows them to manage the Senate and decide which bills get a floor vote. In June, the conference said it would re-align with Democrats.

Liu, who is also a former member of the City Council, ran unsuccessfully for mayor against Bill de Blasio. He attacked Avella for being part of the breakaway faction.

Both men had union support in their efforts. Avella counted on the Patrolman’s Benevolent Association and the health care union 1199 SEIU. Liu had supporters including District Council 37, the city’s largest union of public employees, and the New York Hotel and Motel Trades Council. He was also backed by the Working Families Party.

The general election is Nov. 4.

(AP)