Katie Glueck at Politico has an in-depth story on the important role Tennessee could play in deciding who will emerge from the Republican field of presidential aspirants. One key factor is that several of Tennessee's largest TV markets reach beyond the state lines.

The extensive airtime candidates receive here, coupled with a primary calendar change, a solid donor pool and the ideological diversity of the GOP in Tennessee explain why both deeply conservative candidates like Cruz, and politicians like Rubio who appeal to more mainstream Republicans, see a path, and are investing significant time and effort into a state that in previously cycles was largely ignored.