" Speechwriter Richard Goodwin, a driving force in American politics during times of upheaval in the 1960s and the husband of presidential historian Doris Kearns Goodwin, has died at age 86.

Goodwin was a key aide and speechwriter for Presidents John F. Kennedy and Lyndon B. Johnson, crafting messages about civil rights and equality and challenging America to live up to its ideals.

Goodwin died of cancer, the Associated Press reports, citing a statement from his wife. Doris Kearns Goodwin says her husband died on Sunday at their home in Concord, Mass.

"Dick Goodwin led an extraordinary life," former President Barack Obama said on Monday. "He was a clerk on the Supreme Court, a Congressional aide who helped lay bare a national scandal, a speechwriter to President Kennedy – and that was all before his thirtieth birthday."

Obama added, "Michelle and I will always be grateful for our friendship with Dick and his wife Doris, and we offer our most sincere condolences to her, their children, and their grandchildren."

Goodwin's most famous work is the speech he wrote for Johnson to deliver to Congress on March 15, 1965, after civil rights demonstrators were attacked by law enforcement in Selma, Ala.

Often called the "We Shall Overcome" speech for its repeated use of that phrase, the speech's official title is "The American Promise," according to The American Presidency Project.

"I speak tonight for the dignity of man and the destiny of democracy," Johnson said at the start of his speech.

"This was the first nation in the history of the world to be founded with a purpose. The great phrases of that purpose still sound in every American heart, North and South: 'All men are created equal' — 'government by consent of the governed' — 'give me liberty or give me death.' Well, those are not just clever words, or those are not just empty theories. In their name Americans have fought and died for two centuries, and tonight around the world they stand there as guardians of our liberty, risking their lives."

Racism, Johnson said, is an American problem. And he added that it was up to all of its leaders, and all of its politicians and people, to solve it.

Johnson asked, "For with a country as with a person, 'What is a man profited, if he shall gain the whole world, and lose his own soul?' "

In 1966, Goodwin helped to write Sen. Robert F. Kennedy's "Ripple of Hope" speech, delivered in South Africa's University of Cape Town.

"It is from numberless diverse acts of courage and belief that human history is shaped," Kennedy said. "Each time a man stands up for an ideal, or acts to improve the lot of others, or strikes out against injustice, he sends forth a tiny ripple of hope, and crossing each other from a million different centers of energy and daring those ripples build a current which can sweep down the mightiest walls of oppression and resistance."

Decades later, Goodwin worked with Al Gore to write his concession speech for the hotly contested 2000 presidential election.

"While we yet hold and do not yield our opposing beliefs, there is a higher duty than the one we owe to political party," Gore said. "This is America and we put country before party; we will stand together behind our new president."

Goodwin's first brush with the national spotlight came in the 1950s, when he helped the Legislative Oversight Subcommittee of the U.S. House of Representatives that investigated a scam behind a quiz program called Twenty One. That incident became the genesis for the 1994 movie Quiz Show — which Goodwin produced and which was also criticized at the time for overstating his role in breaking news about the rigged show.

In his political career, Goodwin is also credited with coming up with the phrase Johnson used for a suite of social welfare, equality and conservation programs: "the Great Society."

Some of those lofty plans had the most basic of beginnings. David Gergen — an adviser to Presidents Richard Nixon, Gerald Ford, Ronald Reagan and Bill Clinton — once told NPR about an anecdote Goodwin recalled about that famous tagline.

Gergen said that "when he worked for Lyndon Johnson," Goodwin recalled "Johnson calling him to the swimming pool and instructing him to take his clothes off and get in the pool with Johnson.

"And Johnson came over to him like a great whale, and looked at him and said, 'I need a slogan.'"

Noting the link between big ideas and branding, Gergen added, "And that's how they came up with the Great Society."