kate upton phenomenon. Reporter: She heats up this year's cover in a photo hot enough to melt ice. In the revealing picture, she sizzles in bikini bottoms and a fur-trimmed parka. The 20-year-old.... See More
kate upton phenomenon. Reporter: She heats up this year's cover in a photo hot enough to melt ice. In the revealing picture, she sizzles in bikini bottoms and a fur-trimmed parka. The 20-year-old. Reporter: Set pulses racing last year. Now he's the swim suit issue's first back-to-back cover girl since tyra banks did it in 1996 and 1997. In this video from last year, she talks about being featured in the magazine. It's an american tradition. When I first got it, it was so exciting. Reporter: While flaunting her curves has made her famous, she's set her sights on turning heads on madison avenue. She's main stream, accessible. The girl next door. But maybe a little hooter. Reporter: She's also had her detractors. Last year, a blogger known as skinny girl called her thick and wrote, she has huge thigs. No waste, big, flat floppy boobs. Her fans snapped to her defense. Cynthia bailey, a former model herself, says upton's appeal is largely due to the fact that she's not superthin. Her body was an example of a healthy, sexy, curvy body. She represents a woman that has that body that you don't often see so much in "sports illustrated." So I was excited to see her. Reporter: For "good morning america," abbie boudreau, abc news, los angeles. Well, she is a beauty. I agree. Let's go to sam and a look
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