HONOLULU, Hawaii (ABC News) -- Sen. Daniel Inouye, the 88-year-old Democrat who has been in office since Hawaii became a state in 1959, has died. His last word was, "Aloha."
He became Hawaii's Senator in 1962, three years after the state joined the United States. He was the longest serving sitting U.S. Senator and the second-longest serving senator in American history.
Inouye's office confirmed the senator's passing to ABC News.
A decorated war hero who lost his arm in battle, in 2000 Inouye was awarded the Medal of Honor for his service in Europe in World War II. He was a champion for veterans and veterans rights.
On Capitol Hill he rose to become Chairman of the Senate Appropriations Committee, which controls the purse strings for the nation and is widely considered one of the most powerful positions in government.
As his office put it in the statement announcing his death, "The story of Dan Inouye is the story of modern Hawaii. During his eight decades of public service, Dan Inouye helped build and shape Hawaii."
And he worked hard to bring federal dollars, particularly from the military, to his island state.
He also sat on special committees that investigated Watergate in the 1970s and the Iran Contra affair in the 1980s.
The senator had been sick for some time, hospitalized since early December, and was fighting respiratory complications as work is being done to stabilize his supplemental oxygen requirements.
When he entered the hospital, the senator's office explained that in the late 1960s, Inouye was misdiagnosed with lung cancer and had a sizeable portion of his left lung removed. After living with this his whole life, his office said, about nine months ago his doctors recommended he begin using an oxygen supplement.
In November, Inouye could be seen using oxygen on the floor of the Senate and has been spotted also using a wheelchair at times.
He was treated at Walter Reed Hospital in November for a minor cut to the back of his head after a fall in his apartment.
Inouye's wife Irene and his son Ken were at his side, according to his office. Last rites were performed by Senate Chaplain Dr. Barry Black.
He is survived by his wife, Irene Hirano Inouye, his son Daniel Ken Inouye Jr., Ken's wife Jessica, and granddaughter Maggie and step-daughter Jennifer Hirano. He was preceded in death his first wife, Maggie Awamura.