"We've lost the irreplaceable center of our family and joyous light in our lives, but the inspiration of his faith, optimism, and perseverance will live on in our hearts forever," the family said in a statement. "He loved this country and devoted his life to serving it."
His death comes just two weeks after the Aug. 11 death of his sister, Eunice Kennedy Shriver, at 88 -- and less than one month after President Barack Obama named Kennedy as a recipient of the 2009 Presidential Medal of Freedom.
Born Feb. 22, 1932, Edward Moore Kennedy was the youngest son of a former U.S. ambassador to England and younger brother of President John F. Kennedy and Sen. Robert F. Kennedy. He grew up in a large, wealthy Boston Catholic family driven by competition in endeavors ranging from touch football to politics.
A liberal Democrat, he shared his brothers' White House aspirations but after both of them died at the hands of assassins and a personal disaster in effect ended his own presidential hopes, he settled in for a long career as a U.S. Senator from Massachusetts.
He was elected to the Senate in 1962, at age 30, and eventually came to be known by admirers and rivals alike as "the liberal lion."
During the current debate on healthcare reform, Republicans in the Senate observed that Kennedy's presence was missed, given his record of accomplishment on social issues.
However, his reputation also included reports of womanizing and drinking and problems at home. Ted Kennedy, who was married to Victoria Reggie at the time of his death, was formerly married to ex-model Joan Bennett Kennedy. In 1981, he and wife Joan, who had been plagued by alcoholism, were divorced after a 22-year marriage.
The haunting experience that had an indelible effect on his career occurred July 18, 1969, when he drove his car off a narrow bridge on Chappaquiddick Island, Mass., near Martha's Vineyard, landing upside down in a 10-foot deep channel. He survived but his only passenger. Mary Jo Kopechne, an aide to his late brother Robert, was drowned.
Unable to save her, he waited 10 hours before reporting the accident, bringing him some harsh criticism and forged another link in the Kennedy family chain of tragedies, one that was with him the rest of the way.
During his time in the Senate, he was a major advocate for civil rights, voting rights, immigration reform, fair housing, consumer protection, national healthcare, AIDS, abortion rights and gun control.
Kennedy's reputation as an effective legislator was already in place two decades ago when Sen. Orrin Hatch, R-Utah, said in 1990 Kennedy was "becoming the statesman that we all hoped he would be."
"Whether you agree with him or not, he's become one of the all-time great senators," Hatch said in 1990.
He was a leading opponent of former President George W. Bush's war in Iraq, calling it Bush's Vietnam and telling CNN Bush had taken the United States to war under false pretenses.
Kennedy's political opponents made extensive use against him of a cheating scandal that prompted Harvard University officials to ask him to leave the school from which his father and brothers had graduated. Kennedy admitted having a friend take his Spanish examination in his freshman year.
He enlisted in the Army and served for two years before returning to Harvard and graduating with honors in 1956.
He ran twice for president, opposing Democratic incumbent Jimmy Carter in 1979 before pulling out and losing the Democratic nomination in 1984 to former Vice President Walter Mondale.
In 1991, Kennedy's oldest son, Edward Jr., who had lost a leg to cancer when he was 12, admitted he was being treated for alcohol abuse. A few months later, Kennedy's other son, Patrick, admitted he had been treated at a drug rehabilitation center in 1986.
Patrick eventually was elected to Congress from Rhode Island, and struggled with substance abuse in later years as well.
"You don't have to be a United States senator to make a difference," Edward Kennedy once said. "All you have to do is care." (c) tPC (c) UPI