Alex and Sierra
Watch Their Performances Week By Week To See How They Won Over America
Britney Spears' "Toxic"
John Travolta & Olivia Newton-John's "You're The One That I Want"
Robin Thicke's "Blurred Lines"
Marvin Gaye's "I Heard It Through The Grapevine"
Ed Sheeran's "Give Me Love"
Robert Palmer's "Addicted To Love"
One Direction's "Best Song Ever"
Taylor Swift's "I Knew You Were Trouble"
Destiny's Child's "Say My Name"
A Great Big World's "Say Something"
Of Monster And Men's "Little Talks"
Sara Bareilles' "Gravity"
Glen Hansard and Markéta Irglová's "Falling Slowly"
Passenger's "Let Her Go"
Ed Sheeran's "Give Me Love" (2nd Time)
Leona Lewis' "Bleeding Love"
A Great Big World's "Say Something" (2nd Time)
Mariah Carey's "All I Want For Christmas Is You"
John Newman's "Love Me Again"
And The Winner Of The X Factor USA Season 3 Is....
Go Download Their Performances On iTunes
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