Kennedy died at his Cape Cod home after a long battle with brain cancer. He was 77.
Kennedy became a Senator in 1962, and gained even greater fame after his brothers, President John F Kennedy and New York Senator Robert Kennedy, died in assassinaitons in 1963 and 1968.
Kennedy made a couple of unsuccessful runs for the Democratic presidential nomination, but it in the end his long run in the Senate may made him the most influential in shaping America's laws.
Kennedy was famous for his ability to pass legislation by reaching across party lines. One of his best-known allies was conservative Utah Republican Orrin Hatch.
Kennedy also made a deal with President Bush that put his mark on the No Child Left Behind law. After Kennedy helped get it passed, he joined the President at Hamilton High School in Butler County for the signing.
Kennedy's fame brought extra attention to his personal life, one that contained several spectacular crises and challenges. In 1964 he was injured in a plane crash. Several years later one of his sons lost a leg to cancer. In 1982 he divorced his first wife Joan, still a source of controversy at the time in heavily Catholic Massachusetts. He remarried some years later.
The largest crisis was in the summer of 1969 when he drove his car off a bridge in Chappaquidick, MA. Kennedy was able to swim away from the crash, but a passenger in his car, staffer Mary Jo Kopechne, drowned. Kennedy pleaded out to leaving the scene of an accident, but was suspected by many of drunk driving or worse.
In May of 2008, he suffered a seizure and was diagnosed with a malignant brain tumor. He continued in politics, endorsing Barack Obama for President and playing a role in getting him elected.