President Barack Obama called Sen. Edward M. Kennedy a "singular figure" in American history who made the country a "more equal and more just" place for all Americans, including the president himself.
"His ideas and ideals are stamped on scores of laws and reflected in millions of lives: in seniors who know new dignity; in families who know new opportunity; in children who know education's promise; and in all who can pursue their dream in an America that is more equal and more just, including myself," Mr. Obama said from Martha's Vineyard, where he is vacationing with his family.
Kennedy, known as the lion of the Senate, at age 77 after for more than a year. During a Senate career that spanned five decades, he took up issues on behalf of the working class and the poor – health care reform, immigration and civil rights among them.
"For his family, he was a guardian. For America, he was the defender of a dream," the president said.
Mr. Obama praised Kennedy for his work in the Senate, which often involved reaching out to Republican colleagues to work jointly on legislation.
"I can think of no one who engendered greater respect or affection from members of both sides of the aisle. His seriousness of purpose was perpetually matched by humility, warmth and good cheer. He compassionately battled others and did it on the Senate floor for the causes he held dear and still maintained warm friendships across party lines. And that's one reason he became not only one of the greatest senators of our time, but one of the most accomplished Americans ever to serve our democracy."
"The outpouring of love … is a testament to the way this singular figure in American history touched so many lives," Mr. Obama said.
The president also reflected on his personal relationship with the standard-bearer of the Kennedy legacy, saying that he had "the honor to call Teddy a counselor, a colleague and a friend."
Kennedy's endorsement of Mr. Obama during the primary season was widely seen as a critical to the president securing the Democratic nomination. At the Democratic National Convention in Denver last August, Kennedy made a surprise appearance to deliver a speech with a familiar theme:
"The work begins anew. The hope rises again. And the dream lives on," Kennedy said then, echoing the same words he delivered at the Democrat's 1980 convention after his own failed bid for the presidency.
Mr. Obama released a written statement earlier Wednesday, saying "our country has lost a great leader, who picked up the torch of his fallen brothers and became the greatest United States Senator of our time."
Read more on the life and death of Sen. Edward M. Kennedy:
CBSNews.com's complete coverage of Sen. Edward M. Kennedy
"Liberal Lion" Remembered
CBS Evening News Anchor Katie Couric reports on the life of Sen. Edward Kennedy
No Immediate Action on Succession
In His Own Words
"The Last Brother"
Life in the Public's Glare
In Pictures: The Kennedys