We're sitting in the back lounge on Worsham's tour bus that's parked outside Joe's Bar in Chicago, where Charlie is set to headline a Saturday night show. The bar is packed, but the show has been delayed due to an NHL playoff game between the Chicago Blackhawks and the Los Angeles Kings that went into overtime.

Charlie, though, doesn't seem bothered by the delay one bit. An easygoing guy with a friendly smile and a slight Southern drawl that's as relaxed as his demeanor, he sits back and chats easily about his background, his lifelong love of music, and how he came to be one of Nashville's most promising new artists.

If you've heard of Charlie, it could be because you saw him open for Miranda Lambert or Taylor Swift (the latter during her 2011 Speak Now Tour). Or because his new single "Could It Be" is gaining radio airplay and steadily climbing the charts.

"Could It Be" is well worth paying attention to. It's a seamless blend of bluegrass-influenced elements with a smooth, country-rock melody � think Vince Gill meets Keith Urban. It's fresh and wholly contemporary, and it gets in your head and sticks.

And it's also unique. For instance, "the first thing you hear" in the song, according to Worsham, is a "slide mandolin." It's played by session vet Jedd Hughes, and it creates a sound that Worsham describes as "Ravi Shankar meets Bill Monroe."

That mandolin part is also an example of why Worsham, who's proficient in several instruments, chose not to go the Hunter Hayes route (writing, producing, and playing every instrument on every song on his debut) and, instead, bring in some studio players during the Rubberband sessions.