VIDEO: Idina Menzel Talks OSCAR Performance on GMA

On today's GOOD MORNING AMERICA, thousands joined together for an epic coast-to-coast "Frozen" sing-a-long live from Tony Award-winning singer Idina Menzel, to the New York City Children's Chorus, to fans who gathered in Times Square, and viewers around the country who sent in their own heart-warming renditions.

"Frozen" has become a box office behemoth since its November release, but it has also become a musical phenomenon, with its song "Let It Go," striking a chord with millions of people around the world.

In an interview with GMA, Idina Menzel, the Tony Award-winning singer behind the song's original vocals, said she's surprised by the way the song has caught on. "I'm surprised at how big and popular it is, but I as a woman I completely relate to this character and I relate to the idea of a woman or girl and having power and not knowing what to do with it and being afraid of your own power and learning to harness that and own that," she said.

Asked why should thought the song has resonated so much with girls, Menzel replied: "Yeah, it's empowering for me. I can totally understand how girls are gravitating to this song. It's about owning your own power. It's about owning who you are and celebrating what makes you fierce, young girl, and not caring what people think and finally relinquishing and being free."

The film has earned two Academy Awards nominations in the Original Song and Animated Feature Film categories.

Menzel, who will perform the song at The Academy Awards ceremony on Sunday, acknowledged she was nervous for the upcoming performance, adding: "Nerves are good. They keep you alive. This is a dream come true. I've watched many people I admire perform and just to be nominated and a part of it is really surreal for me and I'm just having fun with it."