Former Honolulu Mayor Mufi Hannemann announced Tuesday he will seek Hawaii’s open 2nd district seat.

“This decision to reenter the public arena did not come quickly or easily,” Hannemann said in a statement. “I enjoy my responsibilities as president and CEO of the Hawai‘i Hotel & Lodging Association as we work to strengthen our most important industry. At the same time, during my travels throughout the Hawaiian Islands, people have been urging me to ‘get back in the game’ and ‘return to public office.’”

Hannemann joins Honolulu City Councilwoman Tulsi Gabbard and former Congressional staffer Esther Kia’aina in the Democratic primary. The 2nd district is solidly Democratic and, with President Barack Obama at the top of the ticket, the winner of the Democratic primary will be heavily favored to win the seat in November 2012.

Hanneman ran for governor last year, losing the nomination to former Rep. Neil Abercrombie, who went on to win the general. He had also been mentioned as a potential Senate candidate next year, and his decision to run for Congress further clears the field for the seat of retiring Sen. Daniel Akaka (D).

The top Senate candidates include Rep. Mazie Hirono (D), who currently represents the 2nd district, and former Rep. Ed Case (D). Former Gov. Linda Lingle (R) is expected to announce her future plans this fall.