Congressman Allen Boyd has held the seat for eight years and hasn't faced any serious challengers.
The GOP believes the Vietnam veteran is vulnerable in a district carried by President Bush four years ago. Redistricting since then added more Republicans.
Boyd's seat is among seven races targeted by the Republican National Congressional Committee this year. GOP strategists hope to repeat their success from two years ago when they defeated Democratic U.S. Senator Max Cleland of Georgia, another Vietnam veteran.
The district stretches from the Jefferson County east of Tallahassee toward the military heavy western Panhandle including Bay County.