It happens to all of us -- you hear a song once and it gets stuck in your head all day -- sometimes even longer! So, what song is stuck in Kellie Pickler's head these days? It's not the latest Taylor Swift or Brad Paisley hit -- it's a commercial jingle for FreeCreditReport.com!

"Whoever wrote that did a good job because it's so catchy," Kellie said recently. "It gets in your head and you just can't get it out. That and the 'Five, Five Dollar Foot-Long' [Subway commercial jingle]. My road manager Danny gets so mad at me because I get the FreeCreditReport.com commercials in my head. He gets the Subway commercials. So I'll walk by him if we're in passing out on the road, and he's going to go run an errand, I'll walk by him and go 'Five, five dollar foot long.' He gets so mad! If something's around, he'll throw it at me. We like to pick on each other with the commercial jingles."

And it seems Kellie's not the only one who's had the freecreditreport.com jingle stuck in her head. Earlier this summer, when Blake Shelton opened for George Strait at the new Dallas Cowboys stadium, he busted out a live rendition of the peppy tune with the rapid-fire lyrics for the crowd.

Kellie and her road manager will have plenty of time to keep taunting each other with jingles. In addition to opening for Taylor on her 'Fearless' tour, Kellie's performing several solo gigs throughout the fall.

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