New York City’s biggest government-workers’ union is backing City Comptroller John Liu for mayor.

District Council 37 announced the endorsement Wednesday on the City Hall steps. The union represents 121,000 workers in city government and some state agencies.

Executive Director Lillian Roberts says members were impressed by Liu’s efforts as comptroller to curtail unnecessary spending and the hiring of private contractors for city work.

The Democrat says the endorsement means a lot to him. He says he came to appreciate the union members’ input on issues when he was a city councilman.