Whatever his national standing, Kennedy was unbeatable in Massachusetts. He won his first election in 1962, filling out the unexpired portion of his brother's term. He won an eighth term in 2006. Kennedy served close to 47 years, longer than all but two senators in history: Byrd (50 years and counting) and the late Strom Thurmond of South Carolina, who died after a tenure of nearly 47 1/2 years.
Born in 1932, the youngest of Joseph and Rose Kennedy's nine children, Edward Moore Kennedy was part of a family bristling with political ambition, beginning with maternal grandfather John F. "Honey Fitz" Fitzgerald, a congressman and mayor of Boston.
Round-cheeked Teddy was thrown out of Harvard in 1951 for cheating, after arranging for a classmate to take a freshman Spanish exam for him. He eventually returned, earning his degree in 1956.
He went on to the University of Virginia Law School, and in 1962, while his brother John was president, announced plans to run for the Senate seat JFK had vacated in 1960. A family friend had held the seat in the interim because Kennedy was not yet 30, the minimum age for a senator.
Kennedy was immediately involved in a bruising primary campaign against state Attorney General Edward J. McCormack, a nephew of U.S. House Speaker John W. McCormack.
"If your name was simply Edward Moore, your candidacy would be a joke," chided McCormack.
Kennedy won the primary by 300,000 votes and went on to overwhelmingly defeat Republican George Cabot Lodge, son of the late Ambassador Henry Cabot Lodge, in the general election.
Devastated by his brothers' assassinations and injured in a 1964 plane crash that left him with an injured back, Kennedy temporarily withdrew from parts of public life in 1968. But he re-emerged in 1969 to be elected majority whip of the Senate.
Then came Chappaquiddick.
Kennedy still handily won re-election in 1970, but he lost his leadership job. He remained outspoken in his opposition to the Vietnam War and support of social programs but ruled out a 1976 presidential bid.
In the summer of 1978, a Gallup Poll showed that Democrats preferred Kennedy over President Carter 54 percent to 32 percent. A year later, Kennedy decided to run for the White House with a campaign that accused Carter of turning his back on the Democratic agenda.
The difficult task of dislodging a sitting president was compounded by Kennedy's fumbling answer to a question posed by CBS' Roger Mudd: Why do you want to be president?
"Well, it's um, you know you have to come to grips with the different issues that, ah, we're facing," Kennedy said. "I mean, we can, we have to deal with each of the various questions of the economy, whether it's in the area of energy. ..."
Long afterward, he said, "Well, I learned to lose, and for a Kennedy that's hard." Kennedy married Virginia Joan Bennett, known as Joan, in 1958. They divorced in 1982. In 1992, he married Washington lawyer Victoria Reggie. His survivors include a daughter, Kara Kennedy Allen; two sons, Edward Jr. and Patrick, a congressman from Rhode Island; and two stepchildren, Caroline and Curran Raclin.
Edward Jr. lost a leg to bone cancer in 1973 at age 12. Kara had a cancerous tumor removed from her lung in 2003. In 1988, Patrick had a noncancerous tumor pressing on his spine removed. He has also struggled with depression and addiction and announced in June that he was re-entering rehab.
Kennedy's memoir, "True Compass," is set to be published in the fall.
Associated Press Writers Nancy Benac and Laurie Kellman in Washington contributed to this story.
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