I have no idea, I don't follow the show but TV songs do rather well, I mean the Glee songs blew up the first seasons.
Those were pop songs from a show that targetted teens. Nashville is targetting the older demographic who don't usually buy stuff on iTunes, so the fact that Shotgun made the top 100 is a miracle
I'm just so proud she managed to secure a hit in such an unfamliar format for herself, I really wish she'd hit #1 in the Country charts so I can bully Carson into saying it on The Noise next week.
The song is only available on iTunes until April 27th. For some reason, her Nashville songs are only available for one week. The Real Thing has already been taken off iTunes. Also, there's no streaming available.