Since Affirmed captured horse racing’s Triple Crown in 1978, 11 thoroughbreds have won the Kentucky Derby and Preakness Stakes only to fall short in the final leg, the Belmont Stakes. On Saturday, when I’ll Have Another attempts to join the elite ranks of history’s Triple Crown winners, he’ll be carrying not just 114-pound jockey Mario Gutierrez but the weighty hopes of the sport itself.

■ BREAKING NEWS: I’ll Have Another scratched from Belmont. Details here.

Among those pulling for him will be Affirmed’s co-owner Patrice Wolfson, who sees in I’ll Have Another the same zeal for winning that drove her own chestnut champion past archrival Alydar on Belmont Park’s grueling mile-and-a-half track. She also sees a budding star who might help restore some of the prominence horse racing has lost during its 34-year wait for the next Triple Crown victor.

“I certainly think racing needs a horse that can bring a lot of excitement, and this little guy I think can do that,” Wolfson told reporters during a conference call last week.

The question is: Could I’ll Have Another, the colt with a flair for heart-stopping finishes, capture the public’s imagination the way Affirmed, Seattle Slew and Secretariat did in achieving the Herculean feat of winning three major races in five weeks in the 1970s? Moreover, could a 2012 Triple Crown winner help revitalize a troubled industry? Or has the 21st century, with its endless forms of entertainment and myriad forms of legalized gambling, left thoroughbred racing behind?

Just four months ago, I’ll Have Another was a lightly regarded colt who had been sold as a yearling for $11,000. He was later resold as a 2-year-old for a modest $35,000. But since February, he has done nothing but prove himself a worthy champion. Never the favorite, he has won every race he has entered in 2012 — including the hallowed Kentucky Derby and Preakness Stakes — not with brutish power but with cool and cunning, exploding over the final furlong to get his nose out front at the precise moment it matters.

But the world is far different than it was 34 years ago, as is horse racing’s place in it.

Once mainstream entertainment, thoroughbred racing has become more of a niche sport. Even its passionate followers don’t necessarily go the track anymore; they place wagers in casinos, over their computers or via cell phones instead.

And its romantic allure has been tarnished by reports of performance-enhancing drugs, lax enforcement and the breakdowns of finely bred athletes, such as 2006 Kentucky Derby champion Barbaro.

“Having a Triple Crown winner would help racing and the interest in racing,” said Sally Hill, co-owner of Seattle Slew, speaking on the same conference call. “It’s not going to solve all our problems by any means, but I think it would be a great help to bring that interest back.”

Added Affirmed’s former jockey Steve Cauthen: “I think the whole racing world is just dying to have another great horse come along and capture their hearts.”

‘This was greatness’

Hard times have a way of creating a need for heroes. And at key moments in American history, horse racing’s Triple Crown has supplied its share.

According to author and historian Laura Hillenbrand, whose best-selling 2001 biography, “Seabiscuit: An American Legend,” was made into an Academy Award-nominated movie, it takes a special chemistry to transform an athlete into a cultural phenomenon. The essential ingredients, Hillenbrand wrote in an email exchange, are greatness on the athlete’s part, a story or hook that captivates an audience and a conducive historical setting that makes the athlete’s virtues particularly compelling.

It all came together with War Admiral, who claimed the Triple Crown in 1937.

“He was emphatically great: overwhelmingly fast, game, enduring and consistent,” Hillenbrand explained of War Admiral. “He was magnificently beautiful, a glittering creature. His biggest hook was his hell-for-leather personality: He was so impatient to run that he dragged his handlers to the track, delayed starts endlessly by spinning and plunging, trying to break free and run, and in the Belmont Stakes, burst from the gate so hard that he tore off a chunk of his hoof and ran the entire mile and a half with blood spraying over his belly, yet still won with ease, capturing the Triple Crown and setting an American speed record. People saw that and shivered. This was greatness.”

War Admiral also benefited from perfect timing, Hillenbrand notes, arriving when racing was the country’s fastest growing sport, the only legally sanctioned form of gambling and covered intensely by daily newspapers, radio broadcasts and newsreel documentaries.

“Perhaps most important, America was in the depths of the Depression,” Hillenbrand added. “People wanted to escape through sports heroes, and this glamorous creature was a natural sell. War Admiral was everywhere, he had everything, and he was irresistible. Thus, he transcended racing and became a cultural phenomenon.”

Nearly four decades later, Secretariat did, as well.

In 1973, America was riven by the Vietnam War and mired in the Watergate scandal when Secretariat arrived at Belmont Park in pursuit of the Triple Crown. A strapping and handsome 16.2 hands, Big Red, as the chestnut colt was called, had a personality every bit as large.

He sulked after his rare defeats then stormed back to shatter track records in his next outings. He loved the spotlight, famous for stopping and posing whenever he heard camera shutters click. And he had a heart that was twice the normal size—a fact discovered during his necropsy, which explained his exceptional lung capacity and something about the soul within.

A half-century later, veteran Newark Star-Ledger sportswriter Jerry Izenberg, 81, one of three journalists to chronicle every Super Bowl, describes covering Secretariat’s victory at the Belmont, in which he crushed the field by a record 31 lengths, as one of the greatest thrills of his career.

“You hadda see it!” Izenberg gasps, recounting Secretariat’s unfathomably lead: first 15 lengths, then 20 lengths, then so far ahead that jockey Ron Turcotte turned around in his saddle in disbelief and the TV broadcast went to a split screen to prove there were other horses in the race.

In the glorious aftermath, Secretariat was splashed on the covers of Time, Newsweek and Sports Illustrated the same week — the only horse to complete that particular trifecta. And following his death in 1989, he was the only non-human named to ESPN’s 50 Greatest Athletes of the 20th Century.

“He was a genuine hero when America needed a hero,” Izenberg said of Secretariat. “When you suddenly find you can’t trust anything, you can trust your eyes.”

‘A brilliant horse’

I’ll Have Another’s riveting charge past the favored Bodemeister to win the Kentucky Derby as a 15-1 shot by 11 / 2 lengths was high drama of the razor-thin sort. And two weeks later at the Preakness Stakes, I’ll Have Another sped past Bodemeister on the final stretch again to win at the wire by a neck.

At Three Chimneys Farm in Versailles, Ky., where I’ll Have Another’s sire, Flower Alley, stands at stud, employees are high-fiving and pumping fists, overwhelmed with pride in the son’s achievements. Flower Alley’s date book is suddenly full, too, having jumped from 50 mares on his docket on April 1 to 138 today.

“All we have done for the last 30 days is take phone calls from breeders to breed to Flower Alley,” says the farm’s president, Case Clay. Flower Alley’s stud fee has also doubled from $7,500 to $15,000 since his progeny’s masterful finishes in the Kentucky Derby and Preakness. It will climb higher still if I’ll Have Another, from the stallion’s second crop, wins the Triple Crown, although Clay can’t venture a guess, given that the last comparable figures are 34 years old.

And at Belmont Park, spectators have flocked to I’ll Have Another’s 8:30 a.m. workouts in the run-up to Saturday’s race, according to veteran turf writer Jenny Kellner, who works in the communications department of the N.Y. Racing Association, just to glimpse the plucky 3-year-old and his storied stable pony Lava Man.

“What makes him so exciting is his style of running,” Kellner says. “His past three races have all been by very narrow margins — just thrilling through the stretch. He’s a brilliant horse.”

Said Wolfson, Affirmed’s owner: “Maybe it’s just time. Maybe racing could use a star, and he could possibly be the star.”