Sen. Edward M. Kennedy (D-MA), a giant of liberalism in the latter half of 20th century who was often overshadowed by the memory of his slain brothers, died of brain cancer late Tuesday night in Hyannis Port, Massachusetts. He was 77.

First elected to the senate in 1962 at the age of 30, Kennedy went on to serve in the body for 46 years -- longer than all but two senators in United States history, Sen. Robert C. Byrd (D) of West Virginia and Sen. Strom Thurmond (R) of South Carolina.

Kennedy's long political career was filled with a mix of historic legislative accomplishment, tragedy and recurring scandal. Kennedy was the key legislative mover behind the Immigration and Nationality Act of 1965, which abolished the national origin quotas that had been in place since the 1920s, as well as a key supporter of numerous Great Society programs. Yet his central role in passing this and other path-breaking liberal reforms in the late 1960s was soon overshadowed by the incident on Chappaquiddick Island in 1969 in which the passenger in the car Kennedy was driving, Mary Jo Kopechne, died after he drove off the edge of a bridge.

Kennedy later fought a bitter primary battle against President Jimmy Carter in 1980 but failed to wrest away the nomination. And in the years following he gave up the presidential ambitions that had hung about him like an aura since the death of his brother Robert Kennedy in 1968.

By the early 1990s, with a new marriage to second wife Victoria Anne Reggie, Kennedy began to emerge as an elder statesman of the Democratic party and its often diminished liberal wing. His reputation as a consummate legislator and conscience of his party began to eclipse the burden of his brothers' legacy and personal indiscretions which had cast a shadow over the first quarter century of his senate career.

In the final two years of his life, Kennedy provided critical support which then-candidate Barack Obama used to secure the Democratic nomination and later the presidency. And he lived to see an historic and as yet unresolved political confrontation over comprehensive health care reform, which he called "the cause of my life."

For many, Teddy Kennedy's life, with its highs and lows, will never compare to the heroic, even mythic, reputations of his brothers, John and Robert, both of him were felled by assassins' bullets in their 40s. But the passage of time suggests a more favorable verdict. In contrast to their younger brother, the senate careers of John and Robert Kennedy were brief and relatively undistinguished. And the personal recklessness and indiscipline at the root of the scandals that marred the younger Kennedy's reputation were amply evidenced in his elder brothers' lives, just little known until years after their deaths. Had they lived in the era of unforgiving press scrutiny in which Teddy Kennedy lived most of his adult life, history might remember them quite differently.

In the end, Teddy Kennedy's life was defined by the blessing and curse of longevity, a span of almost eighty years that allowed him to emerge as a legislator and politician vastly more accomplished and influential (in terms of the effects on the everyday lives of ordinary Americans) than either of his brothers but also revealed his personal shortcomings in ways his brothers' never were. Yet by his later years, through a mix of a trademark perseverance, dedication to public service and undeniable accomplishments, his personal story took on an air of redemption, perhaps even transcendence, which is a fitting memorial in death.

Early Wednesday morning, the Kennedy family released the following statement announcing the senator's death ...

"Edward M. Kennedy - the husband, father, grandfather, brother and uncle we loved so deeply - died late Tuesday night at home in Hyannis Port. 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. We thank everyone who gave him care and support over this last year, and everyone who stood with him for so many years in his tireless march for progress toward justice, fairness and opportunity for all. He loved this country and devoted his life to serving it. He always believed that our best days were still ahead, but it's hard to imagine any of them without him."