One of the state’s largest public worker unions, the United Public Workers, is backing U.S. Rep. Colleen Hanabusa in the Democratic primary for U.S. Senate.

The 13,000-member union announced its endorsement at a news conference Wednesday, along with those of six smaller labor unions.

"They want to see somebody who they trust and someone that they feel will always be there to battle for them, no matter what," Hanabusa said after the endorsements were announced.

The move by UPW positions the union on the other side of the Hawaii Government Employees Association, the state’s largest public worker union with 42,000 members, which has endorsed incumbent U.S. Sen. Brian Schatz in the 2014 race.

Both unions are locals under the umbrella of the American Federation of State, County and Municipal Employees international union.

"What many of them have told me is that that’s the reason why they came out as strongly as they did — and some of them against advice of their internationals, whatever it may be — it’s because of the fact that they feel that they know Hawaii best and they know what the people of Hawaii need best," Hanabusa said. "So that is an amazing kind of accolade and compliment."

Dayton Nakanelua, UPW state director, said after the news conference that there was no pressure from the parent union to side with a specific candidate.

"Our international union, AFSCME, is a democratic union and it provides to all its affiliates all the decision-making authority that we need in representing our members throughout the state of Hawaii," Nakanelua said. "So our relationship with our international union is strong. It’s positive."

He said the UPW’s political action committee was unanimous in backing Hanabusa, based on its familiarity with both candidates.

"It’s based on our working history with both the candidates," he said. "She has been a familiar figure to us in the labor movement, but more importantly she has those values that represent all of the people of Hawaii."

Other endorsements for Hanabusa announced Wednesday included those from the Hawaii Longshore Division statewide, Hawaii Laborers Union Local 368, Hawaii Masons Union Locals 1and 630, the HawaiiSheet Metal Workers Union Local 293, and the International Federation of Professional and Technical Engineers Local 121.

The International Longshore and Warehouse Union, Local 142, is among the state’s largest private sector unions with about 18,000 workers. It was not immediately known how many are included in the Longshore division. The other unions represent more than 8,000 public and private sector workers both active and retired.