Here is a list of senators who are up for reelection in 2010.

Who's Up for Reelection in 2010? Full List

Retiring Senators
Ted Kaufman (D) of Delaware
Kit Bond (R) of Missouri
Sam Brownback (R) of Kansas
Mel Martinez (R) of Florida
George Voinovich (R) of Ohio

Democratic incumbents
Blanche Lincoln of Arkansas
Barbara Boxer of California
Michael Bennet of Colorado
Christopher Dodd of Connecticut
Daniel Inouye of Hawaii
Roland Burris of Illinois
Evan Bayh of Indiana
Barbara Mikulski of Maryland
Harry Reid of Nevada
Kirsten Gillibrand of New York
Chuck Schumer of New York
Byron Dorgan of North Dakota
Ron Wyden of Oregon
Patrick Leahy of Vermont
Patty Murray of Washington
Russ Feingold of Wisconsin

Republican incumbents
Richard Shelby of Alabama
Lisa Murkowski of Alaska
John McCain of Arizona
Johnny Isakson of Georgia
Mike Crapo of Idaho
Chuck Grassley of Iowa
Jim Bunning of Kentucky
David Vitter of Louisiana
Judd Gregg of New Hampshire
Richard Burr of North Carolina
Tom Coburn of Oklahoma
Arlen Specter of Pennsylvania
Jim DeMint of South Carolina
John Thune of South Dakota
Bob Bennett of Utah