Johnson City mayor Roe narrowly defeated Davis in the Republican primary by a margin of 50% to 49% (only 500 votes).

[3] Davis was elected in 2006, succeeding retiring congressman Bill Jenkins, winning the Republican nomination over a crowded field which included Roe.

Roe, a retired OB/GYN, was endorsed by several local newspapers, refused PAC and special interest money, and promised not to serve any more than ten years in Congress.

This district lies in the east-central part of the state, based in Knoxville, and is largely coextensive with that city's metropolitan area.

This district lies in Middle and East Tennessee and includes all of Bledsoe, Campbell, Coffee, Cumberland, Fentress, Franklin, Giles, Grundy, Lawrence, Lewis, Lincoln, Marion, Maury, Moore, Morgan, Pickett, Scott, Sequatchie, Van Buren, Warren, and White Counties, as well as portions of Hickman, Roane, and Williamson counties.

Although the 4th is one of the few districts in the nation that is not considered safe for either party, its size and the fact it includes five television markets make it fairly easy for incumbents to tenure themselves in.

This district lies in southwestern Tennessee, located entirely within Shelby County and including most of the city of Memphis.

It has been represented by Democrat Steve Cohen since 2007, who ran against independent candidates Jake Ford, Dewey Clark, and Taylor Shelby Wright.

[4] No Republican filed in this overwhelmingly Democratic district, although Cohen's primary victory assured him of a second term in any case.