When Raine Michaels saw Kate ­Upton rocking a skimpy bikini and down jacket on the cover of the Sports Illustrated Swimsuit issue in 2013, her dream to become a model was cemented.

“She’s been one of my idols since I was 13. She has a more voluptuous figure and we have similar body types,” Raine recalled at her photoshoot for The Post, at the Williamsburg Hotel. “When I saw [Upton] in that Antarctica shoot, I was like, ‘We kind of look alike. I see my body type being represented in the modeling world.’ She represented everything I want to represent.”

Now, Raine is the one making ice melt.

The daughter of Poison lead singer Bret Michaels, she was crowned a model-search finalist in this year’s Swimsuit Issue, posing for the mag in barely-there bathing suits in the Bahamas.

“It was honestly insane,” said the 19-year-old, who studied journalism at Belmont University in Nashville. (She’s planning to move to New York City in the fall to pursue her modeling career and will take college courses online.)

Despite her famous father’s connections and mother Kristi Gibson’s modeling past, Raine’s path to modeling wasn’t always easy.

She was first signed to an agency at the age of 16 on the condition that she slim down.

“They kept telling me I needed to lose weight — and it was the skinniest I’ve ever been,” said Raine, who was a size 2 at the time. She resorted to twice-a-day workouts and subsisted on chicken and vegetables to meet the agency’s demands.

“I felt like it was the end of the world,” she said. “I was like, ‘I’m fat.’ ”

Eventually, the pressure became too much for the teenager.

“When I kept losing weight and they kept saying I had to lose a little bit more, I was like, ‘I can’t do this. This is me.’ ”

In January, she got tapped by One Management NYC, which happily accepted her curvy glory.

“They were like, ‘We love you as you are. Don’t change,’ ” said Raine. The Sports Illustrated shoot was her first major modeling gig.

“The modeling world is moving away from the one body type,” said Raine, who stays fit with hot yoga and added hot-boxing classes to her routine prior to her debut magazine shoot. (“It’s kind of hell during it, but afterwards it feels great,” she said of the workout.)

Raine was born in Los Angeles, then moved to Vancouver for five years before heading to Arizona “because my dad liked the weather there for some reason,” she said. She and her mom, dad and younger sister, Jorja, lived there for eight years before moving back to L.A. in time for her high-school years.

While Raine says her childhood was fairly normal, there were moments, she admits, that were pure rock ’n’ roll.

“One time, I was singing backup for Lynyrd Skynyrd at one of my dad’s concerts. My dad just asked Lynyrd if his daughters could go on stage and sing ‘Sweet Home Alabama.’

“People treat [me] differently once they know who my father is. Not everyone, because I have such good friends and most of their moms or dads are famous,” she said. “But if I get introduced to someone as ‘Raine,’ they are like, ‘Oh, nice to meet you.’ If it’s, ‘This is Bret Michaels’ daughter,’ it’s a whole ’nother level. I can tell if they are bull s–tting.”

The upside of having a rock-star father? He’s seen it all.

“Not all dads are super-supportive of their daughters going out to model in skimpy bikinis,” Raine acknowledged. “But [my dad] has been in this ­industry for so long, he knows it’s not weird.”

If modeling doesn’t work out, Raine says she would love to work in entertainment journalism and model her career on that of “Saved by the Bell” star-turned-“Extra” host Mario Lopez.

And, there’s always reality TV.

Her father infamously starred on the “Bachelor”-like VH1 show “Rock of Love with Bret Michaels” when Raine was younger.

“I haven’t watched it. I’ve seen clips of it. But I don’t want to see it. It’s still my dad!” she said, adding that he and her mom, who have been on-and-off for nearly 25 years, “are good.”

In 2010, Raine herself appeared on her dad’s short-lived VH1 docu-series, “Bret Michaels: Life as I Know it.” Recently, someone from the new CBS reality dating show “Love Island” asked her to audition.

“Maybe in a few years,” Raine said with a laugh. “I don’t know if I’m catty enough.”

After all, Raine is all about positivity — even in the face of negativity.

She even kept her cool after an Instagram follower lambasted her chances of winning the Sports Illustrated competition, commenting: “The only competition you’re going to win is a pie-eating competition.” (Earlier this month, 22-year-old Brooke Nader was announced as the winner.)

Recalled Raine: “I commented back, ‘Unfortunately, I’m gluten-free.’ ”

Photos: Brian Zak/NY Post; Stylist: Bree Bonagofsky; Hair: T. Cooper/crowdMGMT using ECRU NY; Makeup: Markphong Tram/abtp using Laura Mercier; Location: The Williamsburg Hotel, 96 Wythe Ave, Brooklyn.