Alabama
Incumbent: Jeff Sessions (first elected in 1996)
CQPolitics Rating: Republican Favored
Joanna Anderson
Alaska
Incumbent: Ted Stevens (first appointed in 1968)
CQPolitics Rating: Safe Republican
Rachel Kapochunas
Colorado
Incumbent: Wayne Allard (first elected in 1996 — retiring)
CQPolitics Rating: No Clear Favorite
Greg Giroux
Georgia
Incumbent: Saxby Chambliss (first elected in 2002)
CQPolitics Rating: Republican Favored
Rachel Kapochunas
Idaho
Incumbent: Larry E. Craig (first elected in 1990)
CQPolitics Rating: Safe Republican
Jesse Stanchak
Kansas
Incumbent: Pat Roberts (first elected in 1996)
CQPolitics Rating: Safe Republican
Nathan Levinson
Kentucky
Incumbent: Mitch McConnell (first elected in 1984)
CQPolitics Rating: Safe Republican
Greg Giroux
Maine
Incumbent: Susan Collins (first elected in 1996)
CQPolitics Rating: Leans Republican
Laura Blinkhorn
Minnesota
Incumbent: Norm Coleman (first elected in 2002)
CQPolitics Rating: Leans Republican
Marie Horrigan
Mississippi
Incumbent: Thad Cochran (first elected in 1978)
CQPolitics Rating: Safe Republican
Rachel Kapochunas
Nebraska
Incumbent: Chuck Hagel (first elected in 1996)
CQPolitics Rating: Safe Republican
Nathan Levinson
New Hampshire
Incumbent: John E. Sununu (first elected in 2002)
CQPolitics Rating: Leans Republican
Rachel Kapochunas
New Mexico
Incumbent: Pete V. Domenici (first elected in 1972)
CQPolitics Rating: Safe Republican
Marie Horrigan
North Carolina
Incumbent: Elizabeth Dole (first elected in 2002)
CQPolitics Rating: Leans Republican
Kathleen Hunter
Oklahoma
Incumbent: James M. Inhofe (first elected in 1994)
CQPolitics Rating: Republican Favored
Rachel Kapochunas
Oregon
Incumbent: Gordon H. Smith (first elected in 1996)
CQPolitics Rating: Leans Republican
Jesse Stanchak
South Carolina
Incumbent: Lindsey Graham (first elected in 2002)
CQPolitics Rating: Republican Favored
Marie Horrigan
Tennessee
Incumbent: Lamar Alexander
(first elected in 2002)
CQPolitics Rating: Republican Favored
Rachel Kapochunas
Texas
Incumbent: John Cornyn (first elected in 2002)
CQPolitics Rating: Republican Favored
Greg Giroux
Virginia
Incumbent: John W. Warner (first elected in 1978)
CQPolitics Rating: Republican Favored
Greg Giroux
Wyoming
Incumbent:
Michael B. Enzi
(first elected in 1996)
CQPolitics Rating: Safe Republican
Marie Horrigan