The 76-year-old senator walked onstage to a standing ovation and leaned lightly on a cane. He made no mention of his battle with cancer but sounded a reflective note toward the end of his eight-minute address.

"We know the future will outlast all of us, but I believe that all of us will live on in the future we make," Kennedy said. "I have lived a blessed time. Now, with you, I look forward to a new time of aspiration and high achievement for our nation and the world."

In being honored at a special convocation, Kennedy joins a select group that includes George Washington, Winston Churchill and Nelson Mandela.

Supreme Court Justice Stephen Breyer, a former Kennedy staffer, spoke at the ceremony, and Vice President-elect Joe Biden was among those in attendance. The event had been scheduled for last spring but was postponed as the senator recovered from surgery to treat a malignant brain tumor.

Kennedy devoted nearly a third of his speech to the election of Barack Obama, describing the election of the first African-American head of state as a giant step forward in U.S. history, and one that marks a new beginning for the country.

He said he was "proud to have played a small part" in the historic election. Kennedy gave Obama a key endorsement during his hard-fought Democratic primary against Sen. Hillary Rodham Clinton.

"There is no other time when I would rather receive this honor than this year — at this turning point in American history," he said.

Kennedy also defended his reputation as the "liberal lion" of the Senate, where he has served for 46 years.

He quoted his brother, former President John F. Kennedy, saying: "If by a liberal, they mean someone who looks ahead and not behind ... someone who cares about the welfare of the people — their health, their housing, their schools, their jobs, their civil rights ... then I am proud to say I am a liberal."

Kennedy graduated from Harvard in 1956 and was elected to the Senate six years later to fill the seat held by his brother before he was elected president.

Breyer, a former assistant professor at the Harvard Law School, introduced himself not as a member of the Supreme Court, but as a "former member of the Kennedy staff" who cut his political teeth working in the senator's office.

He said he learned key lessons from Kennedy, including how to work across political divides.

"He'd say be generous with the credit," Breyer said, "If you're successful there'll be plenty of credit to go around, and if you're not successful, who wants credit for that?"

Breyer ticked off a list of some of Kennedy's legislative successes, including his push to foster neighborhood health centers and to expand health care for children and the mentally ill.

During his comments, Kennedy recalled his love of sailing in the waters off Cape Cod, a metaphor for what he said was the next great adventure in the nation's history.

"I have believed that America must sail toward the shores of liberty and justice," Kennedy said. "There is no end to that journey, only the next great voyage."