Kelly Clarkson and Carrie Underwood have one big thing in common, and it isn't the fact that they both are blondes.

The two, of course, are both super-successful products of the hit reality show American Idol, something that Clarkson paid tribute to on Wednesday (Oct. 2) when she belted out a version of Underwood's crossover 2006 hit "Before He Cheats" to her audience at the Kelly Clarkson Show.

Clarkson gave a smokier edge to the already smoky song, making it a bit of her own while still keeping it in Carrie's lane. The crowd at the taping, of course, was enthusiastic as could be, with everyone grinning and clapping along to Clarkson's groove.

Although Underwood's single spent a record 64 consecutive weeks on the Billboard Hot 100 charts, and Underwood herself holds court as the highest-selling Idol of all time, Clarkson still has the distinction of being the very first, inaugural Idol winner of all. She won the first season in 2002, a full three years ahead of Underwood, who won the title in 2005.

We don't think either of the superstars are keeping score, however, as both are too busy to take notes. Underwood is currently on her Cry Pretty Tour 360, and the talk show is just one of the many things on Clarkson’s plate right now. Not only is she a mother of four, but she also starring on The Voice this season alongside Blake Shelton, Gwen Stefani and John Legend.

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