MIDDLETOWN, Conn. (AP) – Filling in for Sen. Edward M. Kennedy and tying himself to the family’s legacy, Democratic presidential candidate Barack Obama urged college graduates Sunday to “make us believe again” by dedicating themselves to public service.

“We may disagree as Americans on certain issues and positions, but I believe we can be unified in service to a greater good. I intend to make it a cause of my presidency, and I believe with all my heart that this generation is ready and eager and up to the challenge,” Obama told Wesleyan University’s Class of 2008.

The Illinois senator peppered his speech with references to the Kennedy legacy: John F. Kennedy urging Americans to ask what they can do for their country, the Peace Corps and Robert Kennedy talking about people creating “ripples of hope.”

He devoted special attention and praise to Edward M. Kennedy, the longtime Massachusetts senator who had planned to deliver the graduation address but backed out last week after he was diagnosed with a cancerous brain tumor.

Obama, who leads in the race for the Democratic presidential nomination, said he and Kennedy had talked last week about Obama delivering the speech. Kennedy has endorsed Obama in the nominating contest against fellow Democrat Hillary Rodham Clinton and has campaigned for him.

Obama said Kennedy has helped provide health care to children, given parents leave time to spend with new babies, raised the minimum wage and let people keep health insurance when changing jobs “and I have a feeling that Ted Kennedy is not done just yet.”

Kennedy’s stepdaughter, Caroline Raclin, is a member of Wesleyan’s Class of 2008. Her mother, Kennedy’s wife, Vicki, attended the ceremony.

Obama, with a presidential campaign appealing to youth and emphasizing change, often evokes comparisons to the Kennedys, particularly Robert Kennedy and his 1968 bid for the White House.

Clad in a black academic robe, Obama received an honorary doctorate. Some of the graduates had stencils of Obama’s face and the word “hope” – a theme of his campaign – on their mortarboards.

Only briefly did Obama veer into campaign territory, rattling off a list of education changes he promised to make as president. The rest of the 25-minute speech urged students to focus on more than “the big house and the nice suits and all the other things that our money culture says you should buy.”

“At a time of war, we need you to work for peace,” Obama said. “At a time of inequality, we need you to work for opportunity. At a time of so much cynicism and so much doubt, we need you to make us believe again. That’s your task, Class of 2008.”

AP-ES-05-25-08 1428EDT