Crystal Bowersox Performs 'Up to the Mountain' on 'American Idol' Season Nine

Crystal's coronation song was Patty Griffin's Martin Luther King tribute "Up to the Mountain (MLK Song)," which Bowersox sang while strumming her beat-up acoustic, dipping and swaying through her broad range and owning the song as if she wrote it.

(The song wasn't new to the "Idol" stage: Kelly Clarkson performed it with Jeff Beck during 2007's "Idol Gives Back" show.) Hitting a sustained, powerful note and putting her busker's passion into the emotional lyrics like her next meal depended on it, MamaSox ended the show with a powerful display of why she's been this season's front-runner since she first stepped on the stage with the top 12.

The song is called "Up to the Mountain (MLK Song)," originally written by Patty Griffin, and MamaSox absolutely killed it. Sitting on a stool with her guitar, the song started slowly and, from the first note, perfectly fit the singer's style. Her raw vocal power was on full display, a soul- and gospel- and folk-tinged vibe that establishes her as a sort of combination of Janis Joplin and Tracy Chapman for the 21st century. Her connection to the lyrics — inspired by Martin Luther King Jr.'s iconic 1968 "I've Been to the Mountaintop" speech — was unmistakable as she sang, "Sometimes I feel like I've been nothing but tired/ And I'll be working till the day I expire."