Fashion & Beauty

Kate Upton is the new Marilyn

Fashion insiders liken Upton’s sexy star wattage to that of Marilyn Monroe. At A February 2012 appearance on David Letterman’s late show, Upton (right) channeled Monroe’s iconic pose in “the Seven Year Itch” (left). (INF)

After some skateboarding, joke-telling and dancing on the Santa Monica Pier, curvalicious model-of-the-moment Kate Upton boarded an amusement-park ride while shooting her July 2012 GQ cover.

“She’s riding on that, in her bikini, and her top comes off,” recalls GQ bookings director Richard Blandino. “It was hilarious. She was cracking up the whole time, and we pretty much got thrown off the pier.”

PHOTOS: KATE UPTON

It’s that kind of sexy nonchalance that has made 20-year-old Upton an anomaly in the all-too-serious (and all-too-thin) world of fashion.

Oozing the sort of sex appeal and curves that normally pigeonhole models as bikini-only babes, Upton has rocketed from starring in greasy Carl’s Jr. ads to snagging high-fashion spreads with photographers Terry Richardson, Bruce Weber and Steven Meisel — and all within a year’s span.

And she’s turning up the heat in 2013: She’s landed Ryan Gosling’s theatrical agent, Ilene Feldman, and there are rumors that Upton is in the running to score an American Vogue cover as early as April — a huge coup considering that the last model to grace the fashion bible’s cover was Kate Moss, in September 2011.

“She has those wonderful characteristics and sexy kind of moves like Marilyn Monroe had,” says shoe designer Sam Edelman, who cast Upton in his latest campaign.

“She does amazing things with her lips. Amazing things with her body. She’s able to change so quickly from the girl next door to a movie star.”

Upton was so distractingly sizzling in a Mercedes Super Bowl ad teaser, it led to rumors that execs whittled her airtime on game day.

“What’s changed in my life this past year?” Upton mused during a break from her Super Bowl duties over the weekend.

“An easier question would be, ‘What’s the same?’ My life has changed completely, but for the better.”

Last year, the 5-foot-10 blonde graced the covers of British Vogue, Sports Illustrated’s 2012 Swimsuit Issue, GQ, CR (former French Vogue editor Carine Roitfeld’s edgy new fashion magazine) and Italian Vogue.

“I feel like the fashion world is still just discovering her,” says Stephen Gan, editor-in-chief of V magazine, which features Upton in a cleavage-baring hotel-erotica story in its January 2013 issue.

“I said to [Upton], ‘I met you a year ago, and I feel like a bomb exploded since,’ ” recalls Gan. “And she said, ‘It feels more like three.’ ”

So how did a girl who got her start as a Miami bikini model rise to high-fashion fame?

As the great-granddaughter of Frederick Upton, one of the founders of the Whirlpool Corp., and the niece of Congressman Fred Upton, Kate was no stranger to the spotlight. Born in Michigan, she grew up in Melbourne, Fla., where she was a world championship horseback rider. She later moved to Miami and was signed by Elite Model Management at age 15. Two years later, she relocated to Manhattan after being tapped by modeling powerhouse IMG.

Ivan Bart, SVP and managing director of IMG Models, now laughs when he recalls how people lambasted him when he signed a commercial-looking Upton in 2010.

“We would make phone calls, and people would say: ‘She’s not our kind of thing, she’s not our look.’ And all our managers at IMG and I would just simply say, ‘Can you please meet her though?’ And when she walked in the door, she would sell herself. You cannot ignore Kate Upton when she walks into a room.”

Upton landed a steady stream of mid-market gigs, including a Dooney & Bourke ad, a 2010-2011 campaign with Guess and the 2011 “Rookie of the Year” award in the Sports Illustrated Swimsuit Issue.

But it was a viral video of Upton doing the “Dougie” at a Los Angeles Clippers game in April 2011 that catapulted her to fame — and helped her land the cover of Sports Illustrated in 2012.

Soon after, she got her second whiff of virtual hysteria when photographer Richardson filmed her dancing in the teeniest of red bikinis. The online clip was so popular, it amassed nearly 1 million views in the first 24 hours and was momentarily pulled from YouTube for being too scandalous.

“At the end, she puts her hand over her face, almost in embarrassment. It’s that vulnerability that makes her win,” says David Lipman, the adman behind the Edelman campaign.

“She’s the American girl we love. She has that sort of electricity to her,” adds Lipman. “We as a culture have craved her for so many years. We just haven’t been able to find her.”

Which may explain her 700,000 Twitter followers — and the fact that women seem to like her nearly as much as men.

“Her female fan base is quite large. We get hundreds and hundreds of letters thanking her for being brave and being out there,” says Bart.

“She’s aspirational to women, and she’s just hot for guys,” he adds.

In a world of angular models, Upton provides a fresh dose of realism for the fashion industry.

“Fashion doesn’t look right when it looks like fashion. It needs to look like something incredible and beautiful and divine that you would see in real life,” says top fashion fotog Sebastian Faena, who has shot Upton for V, Harper’s Bazaar and Muse, an Italian magazine.

“She makes my pictures look more like life, which is what I’m aiming for in the end,” he says. “She’s the model that excites me the most to shoot. If I could, I would shoot the whole year with her and no one else.”

It’s Upton’s ability to straddle the worlds of girlish sex symbol and high-fashion muse that has made her such an aberration.

“It’s very rare for a girl to move from one area of the business to the other, largely due to the fact that fashion models are almost without curves, whereas swimwear girls are celebrated for them,” admits British Vogue Editor-in-Chief Alexandra Shulman.

But once Upton set her sights beyond swimsuits and jaw-dripping burger ads, there was nothing to hold her back.

“It was the right time,” Upton says of her entry into the world of couture. “I never felt like they weren’t accepting of me . . . I was focused on what I knew, like Sports Illustrated and clients like that.”

She was so desperate to attend the May 2012 Met Ball, whose guest list is closely guarded by Vogue edtrix Anna Wintour, that the burgeoning model shelled out $25,000 of her own dough for a seat.

Her audacity (and generosity) helped Upton get herself noticed, sans gyrating bikini video.

“She knows how to play the game,” says style expert Robert Verdi. “It’s like, ‘OK great.’ You want to be there and you want to be equal to anybody in that room? Buy your ticket, and you’re suddenly a player. ”

No doubt, Upton will parlay the same chutzpah when it comes to making herself a known entity in the movie industry.

“I really want a role that I love, and will commit myself to completely,” says Upton. “It’s a blessing that I have the ability to wait for that right role.”

“It’s all for her,” says Lipman of Upton’s growing reach. “She’s beyond the model. She’s way, way beyond the model.”

dschuster@nypost.com