As Peter S. Canellos and his team of "Boston Globe" reporters show in this revealing and intimate biography, the gregarious, pudgy, and least academically successful of the Kennedy boys has witnessed greater tragedy and suffered greater pressure than any of his siblings. At the age of thirty-six, Ted Kennedy found himself the last brother, the champion of a generation's dreams and ambitions. He would be expected to give the nation the confidence to confront its problems and to build a fairer society at home and abroad.

He quickly failed in spectacular fashion. Late one night in the summer of 1969, he left the scene of a fatal automobile accident on Chappaquiddick Island. The death there of a young woman from his brother's campaign would haunt and ultimately doom his presidential ambitions. Political rivals turned his all-too-human failings -- drinking, philandering, and divorce -- into a condemnation of his liberal politics.

But as the presidency eluded his grasp, Kennedy was finally liberated from the expectations of others, free to become his own man. Once a symbol of youthful folly and nepotism, he transformed himself in his later years into a symbol of wisdom and perseverance. He built a deeply loving marriage with his second wife, Victoria Reggie. He embraced his role as the family patriarch. And as his health failed, he anointed the young and ambitious presidential candidate Barack Obama, whom many commentators compared to his brother Jack. The Kennedy brand of liberalism was rediscovered by a new generation of Americans.