Takai was first elected to the Hawaii House of Representatives in 1994, representing the 34th house district of Pearl City, near Pearl Harbor. He won re-election eight more times before shifting to represent the 33rd house district of Aiea in 2012. Takai was Chairman of the House Committee on Culture and the Arts between 1997 and 2000. He also served as Vice Chairman of the House Committee on Higher Education and as Chairman in 2003–2004. Additionally, he was the Chairman of the House Committee on Veterans, Military, & International Affairs, & Culture and the Arts. During the 2005 and 2006 sessions, Takai served as Vice Speaker of the House. Takai left his 20-year tenure as a state representative to become the Democratic nominee for the United States House of Representatives for in the 2014 elections, following incumbent Colleen Hanabusa's decision to run for the United States Senate. He won the election with 51.2% of the vote, defeating Republican former Congressman Charles Djou. In November 2015, he introduced the Atomic Veterans Healthcare Parity Act, extending federal compensation to those made sick by involvement in cleanup operations after bomb tests on Pacific islands.
Committee assignments
Committee on Armed Services
*Subcommittee on Tactical Air and Land Forces
*Subcommittee on Strategic Forces
Committee on Small Business
*Subcommittee on Agriculture, Energy and Trade
*Subcommittee on Contracting and Workforce
Military service
Takai was commissioned as first lieutenant in the Hawaii Army National Guard on July 19, 1999, and worked as the Preventive Medical Officer. He was the Division Chief for Soldiers Services and a School Liaison for the HIARNG. He later became a lieutenant colonel on May 14, 2013. Additionally, Takai served as the President of the Hawaii National Guard Association and the President of the National Guard Association-Hawaii Insurance, Inc. Takai was called to active duty for six months and served as the Hawaii Army National Guard Deputy State Surgeon. He later served as the Company Commander of Charlie Company, 29th Brigade Support Battalion from November 2006 to May 2008. Takai was posted abroad during Operation Iraqi Freedom as the Base Operations Officer at Camp Patriot, Kuwait, from February 2009 to September 2009. Among his numerous awards and decorations, Takai received the Meritorious Service Medal from the United States Army in 2009, the Distinguished Service Medal from the National Guard Association of the United States in 2011, and the Hawaii Distinguished Service Order in 2012.
Illness and death
Takai was diagnosed with a small tumor on his pancreas in late October 2015. On May 19, 2016, he announced that he would not seek reelection because his cancer had spread, but vowed to serve the remaining eight months of his term. He died two months later at his home in Aiea. He was 49. He is survived by his wife, Sami, and their two children. In 2018, he was posthumously inducted into the Hawaii Swimming Hall of Fame.