Carrie Underwood won 'American Idol' in 2005, almost three years after Kelly Clarkson became the first season's champion. Now, thanks to Carrie's three multi-platinum-selling albums, including her 2009 release, 'Play On,' which was accompanied by a 115-city tour, the Oklahoma native has surpassed Kelly's album sales to become the most successful 'Idol' contestant in the show's 10-year history.

The 'Undo It' singer has sold 12,296,000 albums, compared to Kelly's 10,674,000, according to the Hollywood Reporter. In addition, Carrie's digital sales exceeded 18,482,000, which bests Kelly's by more than one million.

This is the first year Carrie has been tops in sales over all other 'Idol' contestants, but while Carrie was battling it out on the 'AI' stage, former judge Simon Cowell famously predicted she would be the most successful contestant ever on the show.

Rocker Chris Daughtry comes in right behind Kelly, with a combined total of more than 17 million in digital downloads. Clay Aiken holds the fourth slot, with almost six million in combined sales, while Fantasia rounds out the top five with just over five million in sales.

Season 5 contestant Kellie Pickler, who came in sixth in the season that ultimately crowned Taylor Hicks the winner, has amassed more than four million in sales, with over three million credited to digital downloads.

Sales tallies aside, Carrie credits the hit show with the intimate interaction she has with fans today. "There's much more of a relationship with me and the fans, because in the beginning it was like, 'Oh, we saw her on TV,'" Carrie explains to The Boot. "It wasn't like there was a background repertoire kind of 'I have her CD. I've seen her in concert. I've followed her.' It was so instant in the beginning, and now I feel like we kind of have a relationship. I feel like I can enjoy it a lot more because I was so in shock in the beginning."

'American Idol' has launched the careers of several country stars, including Danny Gokey, Bucky Covington and Josh Gracin. Kelly Clarkson has also become a Nashville favorite, after lending her vocals to Jason Aldean's recent No. 1 hit, 'Don't You Wanna Stay.'

The finale of the 10th season of 'American Idol' will air on May 24 and 25 at 8:00 PM ET on FOX, with two country music hopefuls, Scotty McCreery and Lauren Alaina, battling it out to be named this season's champ.

Carrie is currently enjoying some time at home with her husband, hockey player Mike Fisher, while she works on her fourth studio album. She'll show off her athletic skills when she returns to the ball field to play in the 21st annual City of Hope Celebrity Softball game on June 21. Tickets can be purchased here.

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