Can You Guess the Artist in This Yearbook Photo?

This artist's hair has been one of the biggest physical transformations from his young age in this photo to what he looks like today. Although it's still dark, and it's a little hard to see details in the yearbook photo, his locks are no longer cropped closely to his head. These days, his mane is curly with a mind of its own, giving the mystery man a tousled and sexy vibe that fans love. Do you know who this artist is?

He grew up in Franklin, Tenn. just south of Music City and his songwriting talents earned him a Grammy nomination for Country Song of the Year just a couple years ago. This singer's sound is compatible with both country and rock radio, and he bridges the gap between the two in a way that converges the genres. Any guesses to who he is?