Jan. 18, 2011 -- Former Democratic vice presidential candidate and Peace Corps founder Robert Sargent Shriver Jr. died today at age 95, family sources told ABC News.

Shriver had long suffered from Alzheimer's disease, a cause that his daughter, former California first lady Maria Shriver, championed in recent years.

President Obama said today hailed Sargent Shriver as "one of the brightest lights of the greatest generation."

"Over the course of his long and distinguished career, Sarge came to embody the idea of public service," the president said in a statement. "His loss will be felt in all of the communities around the world that have been touched by Peace Corps volunteers over the past half century and all of the lives that have been made better by his efforts to address inequality and injustice here at home."

Serving in the Kennedy and Johnson administrations in the 1960s, Shriver ran the War on Poverty and founded or was an early advocate of groups, including Head Start, VISTA, Job Corps, Community Action, Legal Services, Upward Bound, Foster Grandparents and Special Olympics.

President Johnson dubbed him "Mister Poverty" for his work and accomplishments.

"He was a man of giant love, energy, enthusiasm, and commitment. He lived to make the world a more joyful, faithful, and compassionate place," the Shriver family said in a statement. "He worked on stages both large and small but in the end, he will be best known for his love of others."

He was the U.S. ambassador to France from 1968 to 1970. But Shriver's biggest foray into national politics came in 1972 when George McGovern chose him to replace Thomas Eagleton as his running mate on the ill-fated Democratic ticket.

Eagleton had pulled out of the race after revelations that he had been treated for depression and received electroshock therapy. Although McGovern declared that he would back Eagleton "1,000 percent," within a week he asked him to withdraw and picked Shriver, who was well-connected in Democratic politics as a Kennedy family member.

The McGovern-Shriver ticket lost to Richard Nixon and Spiro Agnew in the general election by 23 percentage points, one of the biggest landslides in U.S. presidential history.

Shriver married John F. Kennedy's sister, Eunice Kennedy, in 1953. The two started the Special Olympics, which became a worldwide movement. She died at age of 88 in 2009.

Diagnosed with Alzheimer's disease in 2003, Shriver motivated his daughter to get involved with a four-part HBO documentary, "The Alzheimer's Project."

Maria Shriver talked in 2009 to ABC News about the challenges of her father's disease.

"My kids dealt with the person that was sitting in front of them. Like, 'What are you doing, Grandpa?' And, 'What are you doing today?' And they didn't get into who my father was. They just got into who he was then. And I think that was a very valuable lesson to me," Shriver told "Good Morning America."

"Accept the person that's sitting in front of you. Stop trying to make them who they were. Let it go," she said.

Robert Sargent Shriver Dies

"If Alzheimer's comes into your family, it doesn't just affect the person who gets Alzheimer's. It affects everybody, on every level. ...The cost of it. The emotional wear and tear," Shriver said.

Shriver said then that when she visited her father, he had no idea who she is.

"I think you have to recalibrate yourself every single time you see your father, and you have to introduce yourself to him," Shriver told "GMA."

When she walked into his room, Shriver must tell her father that she is his daughter and that her name is Maria.

"He'll go, 'Oh, my goodness, you are?'" she said.

"At the age of 93, my dad still goes to Mass every day. And believe it or not, he still remembers the Hail Mary. But he doesn't remember me, Maria," she said in testimony before Congress in 2009. "I'd be lying if I didn't admit that still makes me cry."

Sargent Shriver received the Presidential Medal of Freedom from President Clinton in 1994, the United State's highest civilian honor, as recognition for his lifetime of public service.

Shriver was from a generation of Americans that embraced public service and sacrifice. He was a founder of the anti-war group America First before World War II but, when the war started, he enlisted in the Navy and served for five years.

In a 2004 New York Times story on the Peace Corps, he was quoted as telling graduating students at Yale, his alma mater, to break all their mirrors. ''Yes, indeed,'' he said, ''shatter the glass. In our society that is so self-absorbed, begin to look less at yourself and more at each other. Learn more about the face of your neighbor, and less about your own.''

In a speech to a Peace Corps audience in the 1960s, Shriver described his take on life and death.

"The politics of death is bureaucracy, routine, rules, status quo," he said. "The politics of life is personal initiative, creativity, flair, dash, a little daring. The politics of death is calculation, prudence, measured gestures.

"The politics of life is experience, spontaneity, grace, directness. The politics of death is fear of youth. The politics of life is to trust the young to their own experiences."

Shriver is survived by his five children and 19 grandchildren.