Kim's announcement leaves Democrats with a choice between former Mililani state Sen. Randall Iwase and Wai'anae harbormaster William Aila, Jr., whose campaigns have not attracted broad support within the party.

The filing deadline is Tuesday, but no other Democrats have indicated they may enter the race.

Kim had been recruited by party and union leaders over the past several months and his indecision had frustrated many Democrats. He had said he did not particularly want the job of governor but never dismissed talk of a possible campaign.

Several top Democrats had said Kim, 66, a former civil defense administrator in his second term as mayor, would have had the best chance against Lingle.

Lingle has high job approval ratings and a fundraising target of $6 million for her re-election, so the Democratic primary winner will be considered an underdog.

Former Big Island state Sen. Malama Solomon, an ally of Iwase, said this week that she would run for lieutenant governor in the Democratic primary.