U.S. Rep. Mazie Hirono told supporters yesterday that she will run in the Democratic primary for the U.S. Senate next year, seeking to establish herself as a strong voice for Hawaii and the logical heir to fellow progressive U.S. Sen. Daniel Akaka, who is retiring.

In an email to supporters and a video posted on her campaign website, the Hawaii Democrat said she would be an advocate for energy independence, public schools and early childhood education, and for protecting Medicare and Social Security.

Hirono, 63, said she would be a candidate of the people, not insiders and special interests.

"While I’m the candidate in this race, this will always be your campaign," she said in the email. "I’ve never sought public office just to hear the sound of my own voice. I’m running for Senate so that my voice can continue to be your voice."

Hirono will go up against former U.S. Rep. Ed Case in a rematch of their primary for governor in 2002. Hirono edged Case in the primary but lost to Linda Lingle, a Republican who has said she will decide by August whether to run for the U.S. Senate.

"We offer the voters a very clear choice," Case said. "I think it’s a very good decision for them to make on different ways of going about the future for our country."

Former Honolulu Mayor Mufi Hannemann, U.S. Rep. Colleen Hanabusa and Lt. Gov. Brian Schatz have also been considering potential Senate campaigns.

"I’m still seriously mulling the Senate. What her announcement does is present me with another option to consider," Hannemann said of a potential campaign for Congress.

Hanabusa wished Hirono well.

"I am definitely considering a Senate run, but I am still evaluating all my options," she said in a statement. "I will make my decision when I feel it’s appropriate."

Hirono, who was in Washington, D.C., spoke by telephone with Akaka, Hanabusa and U.S. Sen. Daniel Inouye, D-Hawaii, before releasing her statement to supporters.

Inouye, the state’s leading Democrat, repeated his pledge to stay neutral in the primary.

Neither Hirono nor Case is particularly close to the powerful Inouye, so it might be easier for the senator to stay on the sidelines — at least publicly — unless lured by events.

Hirono has broader support than Case among the establishment and liberal Democrats most likely to participate in the primary, so Case — as in previous campaigns — has to bring more moderate, independent and Republican voters into the equation to be competitive.

Hirono and Case offer voters an ideological choice. Hirono is a member of the Progressive Caucus, the most liberal wing in Congress, while Case was part of the moderate-to-conservative Blue Dog coalition when he was in Congress.

A Hawaii Poll taken this month for the Star-Advertiser and Hawaii News Now found Case and Hirono in a statistical tie in the primary. Case was ahead of Hirono on Oahu but behind the congresswoman on the neighbor islands, territory both have represented in the 2nd Congressional District.

Hirono had the highest favorable rating — 64 percent — statewide among the potential Democratic and Republican contenders. More significant, her favorable rating among voters who usually vote Democratic was 83 percent, compared with 62 percent for Case.

Hirono, a former lieutenant governor and state House lawmaker, is an attorney who was born in Japan and became a naturalized citizen in 1959, the same year Hawaii became a state.

She was elected to Congress in 2006, replacing Case, who left for an unsuccessful primary challenge to Akaka.

If Hanabusa does not enter the race, Hirono would likely be able to count on support from national women’s organizations such as Emily’s List, a major fundraising source, as well as local groups such as the Patsy T. Mink Political Action Committee, which honors the legacy of the liberal congresswoman.

Hirono would be the first Asian-American woman elected to the Senate if she won.

"Mazie clearly represents what the party believes in and the issues that we care about," said Jadine Nielsen, chairwoman of the Patsy T. Mink PAC. She represents Hawaii on the Democratic National Committee.

"I don’t want to take away from Ed Case, but I just think Mazie is just more in tune with what our issues are."

State Republicans branded Hirono as ineffective and boring. The state GOP, in a Twitter post, suggested that readers watch her announcement video if they have a hard time falling asleep.

"Mazie has built a record as lieutenant governor and congresswoman of being completely ineffective and has no record of accomplishing anything," said Jonah Kaauwai, state GOP chairman. "So I think it’s interesting that she thinks she deserves a promotion to Senate with that record."

Hirono’s Senate campaign will create an open seat next year in the 2nd Congressional District, which covers parts of Central, Leeward and Windward Oahu and the neighbor islands.

Former state Senate Majority Leader Gary Hooser, who lives on Kauai and now leads the state Office of Environmental Quality Control, Big Island state Sen. Josh Green and Windward state Sen. Clayton Hee are among the Democrats who might be interested.

Hannemann, who lives in Aiea, in urban Honolulu’s 1st Congressional District, might run for the U.S. House if he passes on a Senate campaign.

Former Lt. Gov. James "Duke" Aiona, who lives in Kapolei, said he has not ruled out a possible run. "I’ve learned never to say never," he said.

Former U.S. Rep. Charles Djou said he is not actively planning a campaign next year, and would not run in the 2nd District unless the Reapportionment Commission redraws the boundaries in a way that includes his East Honolulu home.

Several potential candidates might wait until the commission sets new boundaries, which are based on population data from the 2010 census, before making commitments.

Members of Congress do not have to live in the districts they represent. Hirono lives in urban Honolulu, for example, while Hanabusa lives at Ko Olina Resort & Marina in Kapolei.