He represented Tennessee's 1st congressional district, located in the northeastern portion of the state and centered on the Tri-Cities area, but was narrowly defeated in the 2008 primary by Johnson City Mayor Phil Roe.

David Davis obtained a 13-week certification in respiratory therapy from East Tennessee State University in 1979 and received a correspondence A.A.S.

While in the state house, Davis voted aye twice in transportation committee to allow illegal immigrants to apply for Tennessee driver licenses (2001 H.B.

[11] In the November general election, Davis defeated his Democratic opponent, Morristown City Councilman Rick Trent of [12] with 61% of the vote.

In the First Congressional District Republican primary held on August 7, 2008, Davis lost by 500 votes, or less than one percent, to Johnson City Mayor Phil Roe.

[13] During the campaign, Roe attacked Davis as an ineffective politician who had sold out to special interests and accepted contributions from oil companies during a summer of record gasoline prices.

While Davis filed two bills within the U.S. House of Representatives as the original sponsor (one Davis bill was to create a federal "American Eagle Day"), he signed on as cosponsor to other pending legislation including H.R.621, a House resolution that sought to "...amend part B of title XVIII of the Social Security Act to restore the Medicare treatment of ownership of oxygen equipment to that in effect before enactment of the Deficit Reduction Act of 2005.

"[16] In 2007, Davis also cosponsored H.R.1398 to amend the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 by providing that manure shall not be considered to be a hazardous substance, pollutant, or contaminant.