Young Gary Hart aides Martin O’Malley, left, Doug Wilson, Trevor Cornwell, Chris Phillips and Gary Robinson in the San Francisco area in advance of the 1984 Democratic convention. Wilson and Cornwell are among the Hart alumni helping O’Malley in his presidential bid. (Photo courtesy of Debbie Shore)

They’re grayer now and thicker around the middle, with real jobs, families and responsibilities. But they still cling to the idealism that led them to work for Gary Hart’s come-from-nowhere 1984 presidential campaign.

Some three decades later, more than a dozen Hart campaign veterans have latched onto another long-shot candidate. This time, it’s one of their own: Martin O’Malley, who joined Hart as a volunteer shortly before his 20th birthday and later ditched college for a semester to work for the Colorado Democrat’s campaign.

While it includes no real political heavyweights, the network is vital to O’Malley’s effort to topple Hillary Rodham Clinton, who is backed by much of the Democratic establishment and is expected to raise and spend vastly more money than other Democratic hopefuls.

The former Hart contingent offers financial support and expertise in foreign affairs and other areas. And, perhaps most important for O’Malley, the Hart alums are a living reminder that what seems impossible sometimes takes root.

Campaign worker George Appleby, left, in a van with presidential candidate Gary Hart. Appleby met Martin O’Malley, who was also working for Hart, during the 1984 campaign, and they have remained friends. Appleby, a Des Moines lawyer, is now the chairman of O’Malley’s presidential campaign in Iowa. (Photo courtesy of George Appleby)

In Iowa, the nation’s earliest caucus state, O’Malley’s campaign chair is George Appleby, a ­buttoned-down Des Moines lawyer who was Hart’s driver back in the day. In New Hampshire, Hart alum Dan Calegari is introducing the former Maryland governor around, and Jerry Slagle, another Hart veteran, hosted a house party the day after O’Malley launched his White House campaign.

“A lot of people are coming back into the fold,” said Trevor Cornwell, a former member of the Hart posse who runs a tech company in Palo Alto, Calif., and is helping O’Malley raise money in the San Francisco Bay area. “If you’re going to be of help to him, now is the time.”

Like O’Malley, Hart was barely registering in the polls in the summer before the 1984 caucuses. His scrappy, young campaign team nevertheless believed they could take on a commanding front-runner, Vice President Walter Mondale, by arguing that it was time for a new generation of leadership.

They slept on floors and ­couches, living off pizza and beer, in those heady months before the cerebral Colorado senator exceeded expectations in Iowa and scored a shocking upset in New Hampshire, becoming a genuine threat to Mondale. Hart fell short of the nomination that year, but he was the leading Democratic contender for the 1988 nomination until a sex scandal derailed his bid.

O’Malley, too, is “a long shot with a chance,” said Debbie Shore, a former Hart aide who today heads a Washington-based nonprofit group that fights childhood hunger. She also sends regular ­e-mail updates on O’Malley to more than 40 Hart alums.

O’Malley said his time with Hart, which included a couple of months on the ground in southeastern Iowa, “absolutely informed my thinking” about politics, emboldening him to run for mayor of Baltimore in 1999 even though an early poll showed him with “a whopping 7 percent.”

George Appleby, left, with Martin O'Malley at the Iowa vs. University of Maryland game in 2014. Both men worked for Gary Hart in 1984, now Appleby is chairing O’Malley’s Iowa campaign. (Photo courtesy George Appleby)

And it has factored into his calculus about offering himself as a younger, more progressive alternative to Clinton. “That campaign taught me at a very early age . . . that the voters actually care, and they actually listen,” O’Malley said. “They want alternatives, and they want to be engaged.”

After hearing about Hart from friends, the 19-year-old O’Malley found himself reading everything he could find about the candidate. He came away convinced that Hart was the only Democrat who could beat Ronald Reagan in a general election. “The other Democratic candidates seemed so old-school, so out of touch with any sense of where things were headed,” O’Malley said. “And, therefore, so doomed to fail.”

Hart, now 78, says he will back O’Malley’s candidacy, both because he believes the country would benefit from fresh leadership and, “if nothing else, because he supported me.”

Asked O’Malley’s odds of winning, Hart replied: “At this stage, very unlikely. But it was for me, too.”

Hart remembers the guitar the younger man toted around Iowa, an O’Malley trademark that endured through seven years as Baltimore’s mayor and two terms as Maryland’s governor.

“What I recall is how much affection there was for him personally, more so than for me,” Hart said. “Particularly from the farm wives, who loved hearing him sing in their kitchens.”

Others helping O’Malley include Phil Noble, a former opposition research director for Hart who owns a technology consulting firm in the early nominating state of South Carolina; John Pouland, Hart’s former Texas director, who lives in Maryland and chaired O’Malley’s political action committee; and Doug Wilson, who served as Hart’s foreign policy adviser, among other jobs, and later worked as senior Pentagon spokesman during President Obama’s first term. He has been informally advising O’Malley on world affairs.

“When someone you knew 30 years ago calls you up and says, ‘Suit up and get in the game’ — I’m there,” said Noble, who last held a paid political position two decades ago.

The calculus has been more difficult for some Hart alums, especially those who have built a life in politics and developed strong ties to Clinton over the years.

Sen. Jeanne Shaheen (D-N.H.), who served as Hart’s New Hampshire director in 1984, said she pegged O’Malley back then as a future rising star. But she is supporting Clinton in 2016, in part because she’s known the former secretary of state and first lady “maybe even longer than I’ve known Martin O’Malley.”

At 52, O’Malley will have additional political opportunities if he runs a good race, Shaheen added.

Rick Ridder, a Denver-based political consultant who was Hart’s national field director in 1984, said he and O’Malley have spoken several times recently about strategy. But Ridder isn’t ready to commit.

“I feel very conflicted, because I know the Clintons quite well,” he said. “But on the other hand, how often do you have someone who worked for you, who is capable and beginning to find their voice, running for president?”

Some who describe themselves as all in for O’Malley said they are still searching for specific ways to be of assistance. “Physically, it’s way more difficult, because I’m not going to sleep in bathtubs anymore,” said Hal Haddon, a criminal defense lawyer in Denver.

Hart alums say the underdog nature of the first Hart campaign, and the scandal that ended the second, created especially strong ties.

“When your candidate is counted out time and time and time again and manages to nonetheless emerge and shape the debate . . . I think it creates a bond,” said O’Malley, who finished college after Hart’s first loss, worked as field director of Barbara Mikulski’s 1986 Senate campaign — which started her long tenure in the Senate — and then returned to Hart for his second run.

“For the campaign to have ended as it did perhaps made that bond stronger for a lot of us,” O’Malley said. “Because we understood the grief involved in what might have been.”

Hart alums remember O’Malley as indefatigable and persistent. Several recounted the time he was found him asleep in the supply closet at Hart’s Washington headquarters, after he had pulled consecutive all-nighters.

“He would sleep on anyone’s floor,” said James Dwinell, who managed the Hart campaign’s finances. “He would eat peanut butter and jelly sandwiches for breakfast, lunch and dinner.”

O’Malley was once sent to Ohio to enlist 500 volunteers for the campaign, former Hart aides said. He disappeared for a few days, only to be found playing his guitar on the steps of the state capitol — where he had signed up 488 people.

Haddon, who helped managed the floor for Hart at the 1984 Democratic convention, said O’Malley never gave up trying to flip delegates from Mondale to Hart, working “with great earnestness, and little result.”

To some Hart alums, O’Malley’s White House bid feels like a continuation of Hart’s journey. Like Hart, O’Malley has tried to cast himself as part of a new generation of leaders, touting his experience in Baltimore and Annapolis using technology to help govern and deploy resources.

“Martin represents another opportunity to move the ball over the goal line,” said Wilson, the foreign policy adviser.

But O’Malley, the Hart alums say, is better at some of the necessities of politics.

Hart could be awkward with people, didn’t like to raise money and often balked at giving the same speech and sound bites again and again on the campaign trail. O’Malley, by contrast, smiles through just about every public appearance and brings a workmanlike discipline to dialing for dollars and repeating his talking points.

As was the case with Hart, supporting O’Malley requires a leap of faith. And the Hart alums know it. Appleby, O’Malley’s Iowa chair, said he still believes in backing the candidate he thinks is best, rather than the one who right now seems positioned to win.

“I had an idealism then. I think I have an idealism now, certainly tempered by my 67 years,” Appleby said. “If you haven’t had your heart broken in politics, you haven’t really supported anybody.”