Carrie Underwood wins the Fourth Season of 'American Idol'

The fourth season finale featuring Bo Bice and Carrie Underwood aired May 24 May 25, and 37 million votes were cast.

It featured appearances by former auditioners, and celebrity cameos by Kenny G, Rascal Flatts, David Hasselhoff, Kenny Wayne Shepherd, George Benson, Billy Preston, Babyface and Lynyrd Skynyrd. The winner of the competition was Carrie Underwood, who would eventually become the first "Idol" winner to sweep all three major music awards (American Music, Billboard, and Grammy Award) in a single season (for 2006-07).

In a nod to the "Diana knew she'd been eliminated by the performance order" controversy of Idol 3, neither contestant sang the winner's single, "Inside Your Heaven", before the results were announced.