Rachel Crow has one of the most inspirational stories on this season of 'X Factor,' and her performance tonight was one of the best on the competition yet.

"Tonight, I'm thanking my mom and dad for adopting me and all the sacrifices they've made," Crow said during her opening montage. Crow was adopted from an abusive, drug-addled home at a young age but you'd never know it -- the girl radiates positivity. As a result, her beaming mentor, Simon Cowell, wanted a song that was "inspirational rather than sad, because it's an inspirational story."

Crow belted out Yolanda Adams' 'I Believe' and absolutely blew the judges away -- even L.A. Reid, who was hoping to take her down a few notches. "I was looking forward to being critical," Reid admitted. "I wanted to be a mean guy, but then you did that and shut it down. I really loved it."

Nicole Scherzinger agreed: "Rachel, you've made a believer out of me, and I'm sure you've made a believer out of everyone in America," she gushed. "You're such an inspiration ... You're just such a bright light. Thank you for that."

Paula Abdul was just as enthusiastic: "If anyone ever questions that there are angels that exist on earth -- there is you," Abdul said. "You opened the show in such a grand way."

Then there was proud mentor Cowell. In his typical understated fashion, he didn't overdo his praise -- but you can tell he wanted to! "I wasn't sure if we should drop to age 12 for the lowest, but you -- you're the reason we did it." It sounds like Cowell is thankful for Crow. After her mind-blowing performance tonight, he's definitely not alone.

Watch Rachel Crow Perform 'I Believe' on 'X Factor'