WASHINGTON - At the top of his current "to do" list is an errand Harris Wofford dreads.

The former Pennsylvania senator has to tell Hillary Rodham Clinton that he is backing Illinois Sen. Barack Obama for the Democratic presidential nomination.

"If Barack doesn't get it, I will be an enthusiastic supporter of Hillary," said Wofford, a friend of both Clintons. "But Obama has the ability to unite us. He has the transforming vision of what we should do with our politics and our relationship with the world that goes right into the soul of me."

Energetic and engaged as he approaches his 81st birthday, Wofford intends to be active in the presidential campaign, raising money and possibly appearing in primary states like New Hampshire and Iowa where the veteran Democrat has longtime friends.

Wofford is working on a memoir, which is no small task for someone who counts the Kennedys and the Rev. Dr. Martin Luther King Jr. among his former colleagues, who was a special assistant to the president on civil rights, helped found the Peace Corps, served as president of Bryn Mawr College, worked in the administration of Gov. Robert P. Casey Sr., and who, after leaving the Senate, headed the Corporation for National and Community Service, the federal agency that runs AmeriCorps.

After winning a special election in 1991 for the Senate seat of the late John Heinz, Wofford narrowly lost a bid for reelection in 1994 to Rick Santorum, then a Republican congressman.

On Jan. 4, Wofford exercised his privilege as a former member to be on the Senate floor for the swearing in of Bob Casey Jr., who defeated Santorum and whom Wofford has known since Casey was 17 years old.

"What goes around comes around," said Wofford with a grin. "But it really wasn't so much about Santorum's defeat. I was embarrassed that I bequeathed to the Senate someone with whom I disagreed with on so many issues."

After beating him, said Wofford, in part by ridiculing his support for volunteer programs as "sitting around the campfire at taxpayers' expense singing 'Kumbaya,' " Santorum changed his view and championed AmeriCorps. Wofford welcomed the help.

"It was a brilliant statement at the time," Wofford said of Santorum's 'Kumbaya' moment. "Santorum told me he's better known for that than anything else - at least until he started talking about sodomy."

An ardent internationalist who as a high school student in New York City founded an organization of "world federalists," Wofford said he is pleased that Casey is serving on the Foreign Relations Committee.

"It's not his specialty," he said of the junior senator, "but I think he'll be a steady, nonpartisan voice."

Among other activities, Wofford serves as a juror for the Purpose Prize, which awards $100,000 to U.S. citizens over 60 who are social innovators. One recipient last year was former Philadelphia Mayor W. Wilson Goode Sr. for his work in mentoring the children of incarcerated parents.

Wofford spoke in the Washington offices of the Points of Light Foundation, where he serves on the board of the organization founded by George H.W. Bush. Wofford has become good friends with the first President Bush - he flew on the Bush plane to the Atlanta funeral of Coretta Scott King - but he had harsh words for his son.

"I feel sad for George Bush and awful for the country," he said. "It's the same feeling I had when former President Johnson got us deeper and deeper into Vietnam. A macho pride and a lack of intellectual curiosity about the world is something that Bush and LBJ share.

"I think Iraq is a series of tragic mistakes, and the repercussions in our relations with the rest of the world are more serious than with Vietnam," he said.

Wofford praised Obama's early opposition to the conflict in Iraq. He said he was "stirred" by the freshman senator's keynote address at the 2004 Democratic National Convention and called his presidential-launch speech in Springfield, Ill., the best rhetoric he's heard since Kennedy and King.

"What I have really always wanted was a modern equivalent of Lincoln in terms of the words and the human vision," said Wofford.

The former senator, who now lives in Washington, said there was a "question" in his mind as to whether Sen. Clinton can pull the country together.

"I think she would be a very good president," he said of the New York lawmaker. "I'm not going to do anything to be derogatory of her. I think she's gotten better and better.

"But this man has captivated me," he said.

Wofford attended law school at Howard University, was an advocate of King's to President Kennedy, and has worked for many years in the civil-rights movement. Wofford could certainly make a credible claim to understanding the African American experience.

In fact, it was partly Wofford's decision to go to Howard, a mainly black college, that has inspired the working title of his memoir, Slightly Mad.

After then-Attorney General Robert F. Kennedy passed over Wofford to head the civil-rights division, Anthony Lewis of the New York Times pressed Kennedy as to why.

Kennedy, according to Lewis, explained that Wofford was "too emotional" when it came to civil rights.

"Tony, you have to admit," Kennedy told the newsman, "that in some areas Harris is a slight madman."

Contact staff writer Steve Goldstein at 202-408-2758 or slgoldstein@phillynews.com.