Mayoral candidate Kirk Caldwell picked up his third union endorsement in recent weeks as the field for the special election to succeed Mufi Hannemann became official.

Eight candidates are seeking to become Honolulu’s next mayor. The field is headlined by Caldwell, the acting mayor; former City Prosecutor Peter Carlisle; University of Hawaii engineering professor Panos Prevedouros; and City Councilman Rod Tam.

There were no surprises yesterday as the candidate filing deadline passed.

The mayor’s race is one of four special elections required because of incumbents stepping down to run for higher office. Other special elections are being held for city prosecutor and two state Senate districts.

The winner-take-all elections for mayor and prosecutor will be held in conjunction with the Sept. 18 primary.

International Longshore and Warehouse Union Local 142 announced its endorsement of Caldwell yesterday.

"He has experience in every branch of government and at all levels — federal, state, and county," ILWU Oahu Division Director Dave Mori said in a news release. "Kirk’s depth of knowledge and experience is why we need him as our mayor."

Caldwell, who became acting mayor on July 20, has picked up the endorsement of three unions that also support his predecessor, Hannemann, for governor. Those endorsements were made by the State of Hawaii Organization of Police Officers and the Hawaii Fire Fighters Association.

Carlisle has been endorsed by the Hawaii Carpenters Union, the state’s largest construction union, which also has endorsed Hannemann.

Hannemann resigned this month with two years remaining in his term.

Carlisle also had to resign to run, vacating the final two years of his term. Candidates seeking the vacancy include former state Labor Director Darwin Ching, Deputy Prosecutor Franklin "Don" Pacarro and former Prosecutor Keith Kaneshiro.

In the state Senate, Bobby Bunda and Gary Hooser resigned with two years remaining in their terms to run for lieutenant governor.

The race for Senate District 22, Bunda’s seat representing Kaena-Wahiawa-Pupukea, includes one former mayoral candidate, City Councilman Donovan Dela Cruz.

His opponents in the Democratic primary include state House Vice Speaker Michael Magaoay, North Shore Neighborhood Board Chairman Michael Lyons and Gerald Hagino, a former state senator. Charles Aki was the only Republican who filed.

Two Democrats, two Republicans and two nonpartisan candidates are seeking the Senate District 7 seat, representing Niihau-Kauai, being vacated by Hooser.