To be an ex-president is to live forever in the past. You write books and build museums to preserve your great moments, to commemorate a time when you led the free world. Crowds still gather and men in dark suits still hover protectively nearby. But mostly these are vestiges. You're a historic figure now, and that makes living in the present—or making the case for the future—a bit tricky. Bill Clinton knows this better than anyone.

On a cool spring morning, the 42nd president, almost 16 years removed from the White House, was standing on the blacktop outside a school in a blighted section of Oakland. It was the third and final day of the annual conference he hosts for college students, a powwow for the world's young thought-leaders-in-training held under the auspices of his Clinton Global Initiative. A few hundred of the students had gathered now to prettify some playgrounds, and Clinton—dressed in the politician's community-service-casual uniform of a blue pullover and stiff jeans—walked among them. Mostly, he posed for pictures. As he did, I watched one especially assertive student wade into the scrum and stride up to the former president.

“Hi, my name's Emma,” she said, and then explained that she had a question about the Middle East. Clinton's smile dimmed a bit, as if he were bracing for something. But Emma, it turned out, wasn't there for a debate—just a photo, albeit of a certain kind. “There's a really cool picture of you standing behind Rabin and Arafat,” she said, referring to the famous shot of Clinton pushing the Israeli and Palestinian leaders to shake on the Oslo Accords in 1993, “and I was wondering, Could my boyfriend and I re-create that picture with you?”

For a second there, Clinton seemed almost let down, as if, having readied himself to consider the intractable dilemmas of the world, he was reduced to a prop—a wax figure in a historical re-enactment. Quickly, however, his grin returned as they struck the pose. Though Emma and her boyfriend didn't ask for one, he proffered a memory, shoehorned into a joke: “It was a lot harder to convince Rabin and Arafat to shake hands than it was to convince you two.”

Moments later, I approached Clinton with a question of my own—an actual one, about the politics of 2016, about his wife's fight to win his old job. I wanted to know what he made of the kids he was hanging out with that day—and if, considering Hillary's notorious struggles with young voters, he thought they were likely to support her over Bernie Sanders. “I don't know,” he told me, betraying no great affection for the question. “It hasn't occurred to me.”

I offered that most of the students I spoke with were pulling for Sanders. That seemed to goad the former president into an answer, and suddenly a stew of frustrations—about his wife's difficulty reaching young people, about Sanders's attacks on her—seemed to simmer over. “The thing that I believe is that unlike in many places, if we had a debate here, they would listen to both of them,” Clinton told me, his words quick and measured. “Most of these students are here because they believe that the best change comes about when people work together and actually do something. So I think they're much more likely to have their eyes and ears open to everybody and every possibility, which is all I would like for everyone.”

I pressed him about what he meant. Was he angry, I wondered, that people had seemingly long ago made up their minds about Hillary? About him, too? Was that fair? He looked at me, his eyes resolute. “I've already told you enough to read between the lines.”

A few weeks earlier, the good people of Bluffton, South Carolina—their minds open to the Clintons or not—were hustling down to a local gym on a Friday afternoon. A woman in medical scrubs led her little girl by the arm, hurrying her toward the doors before the space grew too crowded. They were there, the mother explained to her daughter, who had been dressed in her Sunday best, to glimpse a piece of “living history.”

WASHINGTON, : This 23 February 2000 file photo shows then US President Bill Clinton (L) and First Lady Hillary Rodham Clinton (R) on the South Portico of the White House for the arrival of King Juan Carlos and Queen Sofia of Spain in Washington, DC. With a planned first run of one million copies, publishing house Simon and Schuster is wagering that Hillary Clinton's memoir of her stormy White House years will fly off bookstore shelves. The much-anticipated book, entitled "Living History," will hit bookstores 09 June 2003, Simon and Schuster said. Mrs. Clinton, now a US Senator from New York, received an eight-million-dollar advance for the book, billed as a candid account of her often tumultuous eight years as first lady, marked in particular by an affair between her husband, former president Bill Clinton, and White House intern Monica Lewinsky. AFP PHOTO/FILES/Stephen JAFFE (Photo credit should read STEPHEN JAFFE/AFP/Getty Images) AFP/Getty Images

Inside, the space was festooned with VOTE FOR HILLARY signs, but candidate Clinton would not be in attendance. It was late February, the day before South Carolina's Democratic primary, and her time was better spent elsewhere in the state, in bigger cities with more voters and greater numbers of TV cameras. Instead, the piece of living history that a few hundred of Bluffton's 15,000 citizens had come to see was her husband, the former president of the United States, who now was ambling to the podium.

People craned their necks and held their phones aloft, and Bill Clinton leaned into the microphone. But when he opened his mouth, words failed to tumble forth. Rather, his vocal cords produced a shivers-inducing rattle. He gathered himself. “I apologize for being hoarse,” he finally croaked. “I have lost my voice in the service of my candidate.”

That seemed the least of his maladies. Up close, his appearance was a shock. The imposing frame had shrunk, so that his blue blazer slipped from his shoulders, as if from a dry cleaner's hanger, and the collar of his shirt was like a loose shoelace around his neck. His hair, which long ago had gone white, was now as thin and downy as a gosling's feathers, and his eyes, no longer cornflower blue but now a dull gray, were anchored by bags so dark it looked like he'd been in a fight. He is not a young man anymore—he'll turn 70 in August—but on this afternoon, he looked ancient.

This is Bill Clinton, on the stump circa 2016. The extravagant, manic, globe-trotting nature of a post-presidency lived large—the $500,000 speeches, the trips aboard his billionaire buddies' private planes to his foundation's medical clinics across Africa—has given way to a more quotidian life spent trying to get his wife into the White House. And this time around, more so than in 2008, Clinton is cast in what even he regards as a supporting role. “He's able to go campaign in the places that, because of the schedule and the pressures on her, she can't get to,” John Podesta, Hillary's campaign chairman, told me.

And so Clinton travels to places like Bluffton on small, chartered planes—or takes the occasional commercial flight (albeit in first class with an aide always booked next to him to avoid chatty seatmates). More often than not, the ex-president finds himself staying in hotels with nothing resembling a presidential suite; he typically overnights in Holiday Inn Expresses and Quality Inns. His aides say he's the least prissy member of his small traveling party—caring only that his shower has good water pressure and that the TV has premium cable so that he might watch San Andreas or one of the Fast & Furious movies before he drifts off to sleep. When he wakes, he often makes coffee for himself in his room.

Of course, he still turns out crowds—especially in these hamlets unaccustomed to political royalty. But on that day in Bluffton, as Clinton began to talk, there wasn't much of the old oratorical genius on display. He recalled his college roommate, a Marine who had been stationed nearby; but what seemed like a quick geographical touch point soon spun into a rambling tale about the man's sister-in-law, who had a disabled daughter who now lives in Virginia. “I watched her grow up,” Clinton told the puzzled crowd. His attempts at eloquence—“We don't need to build walls; we need to build ladders of opportunity”—weren't his best, and when he delved into politically relevant topics, like terrorism, he sounded less like a man who used to receive daily intelligence briefings than like an elderly relative at the holiday table. “The people who did San Bernardino,” Clinton explained, “were converted over the social media.” All the while, his hands—those (with apologies to Donald Trump) truly giant instruments that he once used to punctuate his points—now shook with a tremor that he could control only by shoving them into his pants pockets or gripping the lectern as if riding a roller coaster. For more than half an hour, Clinton went on like this, losing more of the crowd's attention as each minute passed, until a few people actually got up from their chairs and tiptoed toward the exits.