Sen. Edward M. Kennedy addresses the convention in 1980.

DENVER — The emotional climax of the 1980 Democratic National Convention in New York was, to the political world, a speech that resounded for the rest of a bitter election campaign that would end with the defeat of President Jimmy Carter.

For the mop-topped boy in the blue blazer, seated in the throng with his mother and his older brother and sister, his father’s fiery declaration was to become one of the most potent memories of a life that would lead him into a political career of his own.

“The work goes on, the cause endures, the hope still lives, and the dream shall never die,” Sen. Edward M. Kennedy said to a long, loud ovation at Madison Square Garden as he lost a rancorous fight against his own party’s president.

Patrick J. Kennedy, now a seven-term Democratic congressman from Rhode Island, even remembers the number — “F3C” — of the “open convention” rule that might have swayed the nominating vote in favor of his father, Carter’s challenger, who had finished the primary season “on a roll,” with victories in key states such as New York and California.

“I can remember so vividly feeling very emotional,” Patrick Kennedy said in a telephone interview yesterday as he readied for the flight to Denver as a Barack Obama supporter who encourages comparisons between the young Illinois senator’s campaign and that of his late uncle, President John F. Kennedy.

“I was breathing a sigh for my father that night that he had come up short,” Kennedy recalled. “Yet I felt such great pride that there was such overwhelming support for him at that time.”

Tonight a multitude of Democrats will share something of that mingled sadness and pride, and as the convention opens with a tribute to the elder Kennedy — “the liberal lion,” as he has so often been identified in the news bulletins since his seizure last spring and the subsequent diagnosis of brain cancer.

There may be commentators who will compare the divided convention of 1980 to this week’s gathering, where the main suspense is over Obama’s efforts to win the support of disappointed delegates who are committed to Sen. Hillary Rodham Clinton — and of the millions of Clinton voters they represent.

Patrick Kennedy said this year’s fight within the Democratic family bears little comparison to the “vitriolic” Carter-Kennedy contest. “Barack Obama is so dispassionate — almost to a fault” that the 2008 Democratic campaign never became so personal.

“The rough-and-tumble of the primaries — that all goes with the territory,” Kennedy said. So does mending fences, he added. Rosalynn Carter, the former president’s wife, is a close and valued ally in Patrick Kennedy’s campaign for legislation to aid the mentally ill.

Such expressions of healing and hope will be a big theme of tonight’s tribute to Ted Kennedy, who has pursued a national health insurance system from the 1980 presidential campaign, to the collapse of then-President Bill Clinton’s health-care initiative, to support for Obama’s health-care plans.

The irony of Kennedy’s medical crisis has not been lost on family members and fellow Democrats. But he has, by all accounts, maintained his customary high spirits and had pushed hard to return to work — possibly here in Denver. Family members and convention officials have been silent on whether the senator will appear tonight.

“It would be quite thrilling for all of us if he were there,” said House Speaker Nancy Pelosi, of California.

Pelosi, who grew up in politics as the daughter of a onetime mayor of Baltimore, witnessed John F. Kennedy’s nomination for president — and sees parallels to this week’s proceedings. “I was there at the 1960 convention with my parents at the Los Angeles Coliseum,” Pelosi told reporters Saturday.

Pelosi linked Kennedy’s memorable open-air speech with Obama’s address Thursday night at an outdoor football stadium here, Invesco Field at Mile High.

Caroline Kennedy told NBC’s Tom Brokaw on Meet the Press yesterday morning that she has seen her uncle often since he underwent treatment for cancer. “He’s just amazing,” she said. “He’s really doing incredibly well,” talking politics with all comers, maintaining his sense of humor and doing interviews with director Ken Burns for the 8-minute video tribute that will be aired tonight as the convention opens..

Caroline Kennedy was the first member of her family to endorse Obama last winter and became part of the inner circle that advised him on the choice of his running mate. She joined her uncle and her cousin Patrick to introduce Obama — and symbolically confer the Kennedy mantle upon him — at a tumultuous rally at American University, in Washington.

“For a lot of our family, it’s going to be incredibly emotional,” Caroline Kennedy said of the tribute tonight. Her three children will be on hand with a large company of Kennedy aunts, uncles and cousins. For the children of Robert F. Kennedy, it will be a moment to recall the presidential campaign four decades ago that was cut short — like his brother’s time in the White House — by an assassin’s bullet.

Another theme of tonight’s tribute — which will set the stage for Michelle Obama’s remarks about her husband and their family — is striving against adversity.

“My dad would always say when I was growing up, ‘From those to whom much is given, much is expected,’” said Patrick Kennedy. In their family, that meant that when his brother, Edward M. Kennedy Jr., lost a leg to cancer as a young man, their father would cite their access to good medical care as a reason for striving to spread such gifts to the less fortunate.

It is not always an easy admonition to follow, Patrick Kennedy said, harkening back to the 1980 convention tableau that featured his mother, Joan Kennedy, who has struggled with alcoholism for most of her life. Unlike Teddy Junior’s cancer, Patrick said, “there was the other illness in the family that we never did talk about.”

Half a lifetime later, in May 2006, Congressman Kennedy’s drug and alcohol addiction came out of the shadows in the most painful way — with a car crash and an encounter with the Capitol Police. In the time since then, he has often said, one of his principal tools of recovery has been to heed his father’s advice to give something back to society.

Echoing his father’s words in the 1980 speech about the generous medical care given to members of Congress, Patrick Kennedy — who also suffers from bipolar disorder — has argued in hearings across the country that everyone laid low by mental illness and addiction should have access to the kind of treatment that has helped him to recover.

“I hope that is following in my father’s tradition,” he said of his decision to speak up about “the other illness in the family.”

Early this year, Kennedy said, his father gave him all the validation he needed on that score. As the mental health bill came to the floor of the House of Representatives, Ted Kennedy crossed the Capitol from the Senate side and quietly took a seat for a couple of hours as his son’s bill was debated and overwhelmingly accepted.

Tonight, said Patrick Kennedy, it will be his turn to be present for his father.

jmulligan@belo-dc.com