The United Public Workers, one of the state’s most high-profile labor unions, has endorsed Honolulu Mayor Mufi Hannemann for governor.

The public-sector union represents 13,000 blue-collar workers statewide.

"Mayor Hannemann knows the value of UPW members," Dayton Nakanelua, the UPW’s state director, said in a statement. "He has a unique appreciation and understanding of the core services provided by our members, and knows first-hand of the challenges they face. As mayor, Mufi has demonstrated that he can find solutions that benefit the greater good of the community. As governor, Mufi will be our best hope to get state government working again in a way which we all can be proud of."

Hannemann is facing former U.S. Rep. Neil Abercrombie in the Democratic primary.

Abercrombie picked up the endorsement of the Democratic Party of Hawaii’s gay, lesbian, bisexual and transgendered caucus.

The caucus described Abercrombie as the only candidate for governor who has consistently supported civil unions and equal protection. "No other candidate has Neil’s track record for standing up for civil rights and supporting our community," Jo-Ann Adams, the chairperson of the GLBT Caucus, said in a statement.

Jonah Kaauwai, the chairman of the state Republican Party, suggested the UPW endorsement means Hannemann would be captive to unions.

"The first of the Big 4 public unions have spoken today in support of Mufi Hannemann, confirming to Hawaii Hannemann is a politician willing to be bought by special interests," he said in a statement. "Hawaii can expect that if union bosses demand higher wages, Hannemann will hand it to them at the expense of Hawaii’s families and small businesses through higher taxes. The question is, what and how much did Hannemann promise?"