U.S. Sen. Daniel K. Inouye has not endorsed a candidate for governor in 2010, but Inouye's staff yesterday did not dispute Honolulu Mayor Mufi Hannemann's claim that the senator has urged him to run.

Hannemann, who has not officially declared his candidacy but is raising money for a possible campaign, said at a fundraiser in Waikíkí on Wednesday night that Inouye had encouraged him to run in the Democratic primary.

U.S. Rep. Neil Abercrombie, D-Hawai'i, has declared his candidacy and his aides have been working behind the scenes to tamp down speculation that Inouye, the state's top Democrat, was backing Hannemann.

"The senator encourages lots of candidates to run for office," Inouye's spokesman, Peter Boylan, said yesterday from Washington, D.C. "Encouraging people to participate in the democratic process is critical to ensuring healthy competition and healthy competition is good for the Democratic Party. It strengthens the party's ranks and adds depth to the party's bench.

"The senator has not officially endorsed any candidate for governor."

The Democratic Party of Hawai'i typically does not endorse in primary campaigns and top Democrats often straddle the line of an official endorsement even when clearly favoring particular primary candidates.

Speculation about Inouye's preference started after Hannemann won re-election to a second term as mayor last year, when the senator, speaking at the mayor's victory celebration, said: "He may go to Washington, he may go to Washington Place."

Some Democrats were certain Inouye favored Hannemann after the senator's friendly remarks about the mayor in August when the mayor was named distinguished citizen of the year by the Boy Scouts of America's Aloha Council.

There has also been talk in political circles about the distance between the Inouye and Abercrombie camps, particularly during last year's presidential primary. Inouye endorsed Hillary Rodham Clinton and Abercrcombie supported Hawai'i-born Barack Obama in the Democratic primary, leading to some tension over the selection of local delegate slots for the Democratic National Convention.

Hannemann's comments about Inouye Wednesday night, which were first reported by the Star-Bulletin, could have an influence on potential campaign donors swayed by the perception Inouye is behind the mayor.

Abercrombie's aides, however, seized on the lack of an official endorsement.

"Senator Inouye's statement that he is not endorsing any candidate for governor speaks for itself," said Laurie Au, a campaign spokeswoman for Abercrombie. "We respect the senator's decision to remain neutral."