Miss Universe winner Olivia Culpo may be a pageant queen now, but a year-and-a-half ago, the 20-year-old Miss USA was just another sophomore at Boston University.

"My first pageant was [Miss Rhode Island] last October...I was studying acting in college, and I figured [pageants] would help my stage performance and my ability to perform for others, so I just went for it," Culpo told Us Weekly on Thursday, Dec. 20, one day after beating out 88 other women from around the globe for the coveted Miss Universe crown.

"My parents didn't think it was a good idea," she added. "And I ended up getting my dress the night before. It was a $20 Rent-the-Runway gown that was too short [and had] a hole in the back of it."

The judges didn't notice. Or if they did, they didn't care. The accomplished cellist -- who says she used to be "chubby" and a nerd -- won the Miss Rhode Island title that day and then went on to win Miss USA in June and Miss Universe on Dec. 19. And she says none of it would have happened without Giuliana Rancic, who co-hosted Wednesday's Las Vegas event with Bravo's Andy Cohen.

"She is actually one of the reasons why I entered the Miss Rhode Island pageant [last year]," Culpo told Us, noting that Rancic is a former Miss Maryland contestant. "At the time I had been thinking, 'Oh, maybe acting, maybe hosting' -- I knew I wanted to go into entertainment. And I figured if Giuliana did [pageants], and Maria Menounos did Miss Massachusetts…I should give it a shot, too."

"I've been close to Giuliana," the brunette beauty added. "She crowned me in June for Miss USA and she crowned me again last night…I love her so much."

Rancic wasn't the only celeb Culpo admired at the pageant. "Diego Boneta is really hot," she dished to Us. (Boneta was one of the Miss Universe judges, along with Brad Goreski**, Scott Disick**, Nigel Barker, Olympian Kerri Walsh, and others.) "The crush of the week was definitely him. He won."

This article originally appeared on Usmagazine.com: Miss Universe 2012 Olivia Culpo: My Parents Didn't Think Pageants Were a Good Idea