| Incumbent | Party | Office | Reason for not seeking re-election |
| Alabama |
| Governor Bob Riley | Republican | Governor | Open Chair. Term Limit. At term limit |
| Congressman Terry Everett | Republican | House CD 2 | Open Seat. 26 September 2007: Announced that he is retiring and will not seek re-election. |
| Arizona |
| Governor Janet Napolitano | Democratic | Governor | Open Chair. Term Limit. At term limit |
| Congressman Richard G. "Rick" Renzi | Republican | House CD 1 | Open Seat. 23 August 2007: Announced that he will not seek re-election. |
| California |
| Congressman Duncan Hunter | Republican | House CD 52 | Open Seat. Running for President in 2008. On 22 March 2007 Congressman Hunter indicated he does not intend to seek re-election. |
| Colorado |
| Senator A. Wayne Allard | Republican | Senate Class 2 | Open Seat. Announced retirement 15 January 2007 effective at the end of this term. |
| Congressman Mark Udall | Democratic | House CD 2 | Open Seat. Candidate for the Senate Class 2 seat in 2008 |
| Congressman Thomas Gerard "Tom" Tancredo | Republican | House CD 6 | Open Seat. Running for President Candidate in 2008. On 29 October 2007 he announced he would not seek a 6th term. |
| Connecticut |
| Senator Christopher J. Dodd | Democratic | Senate Class 3 | Open Seat. On 10 January 2007, Senator Dodd announced that he is running for President in 2008. He has stated that he will not be a candidate for re-election to the Senate in 2010. |
| Delaware |
| Governor Ruth Ann Minner | Democratic | Governor | Open Chair. Term Limit. At term limit |
| Georgia |
| Governor Sonny Perdue | Republican | Governor | Open Chair. Term Limit. At term limit |
| Hawaii |
| Governor Linda Lingle | Republican | Governor | Open Chair. Term Limit. At term limit |
| Idaho |
| Senator Larry E. Craig | Republican | Senate Class 2 | Open Seat. Announced his resignation on 1 September 2007. On 4 October 2007 Senator Craig announced he would retire at the end of his term and not run for re-election. |
| Illinois |
| Congressman Gerald C. "Jerry" Weller | Republican | House CD 11 | Open Seat. 21 September 2007: Congressman Weller stated that he will not seek re-election. |
| Congressman J. Dennis Hastert | Republican | House CD 14 | Vacant Office. Announced retirement on 17 August 2007 effective at the end of his current term. 18 October update: Congressman Hastert announced he would resign before the end of his current term but did not provide a date. 26 November 2007 update: Congressman J. Dennis Hastert resigned his seat today. Illinois Governor Rod R. Blagojevich has 5 days to announce the date of a Special Election to fill the vacant seat. That day could be 5 February 2008. |
| Congressman Ray LaHood | Republican | House CD 18 | Open Seat. 27 July 2007: Announced he will not run for re-election in 2008. |
| Indiana |
| Congressman Julia M. Carson | Democratic | House CD 7 | Vacant Office. We extend our condolences to the family and friends of Congressman Julia M. Carson who passed away on Saturday 15 December 2007 from lung cancer. She was first elected in 1996. On 2 November 2007 Congressman Carson officially requested a medical leave through 14 December 2007. She announced that she had terminal lung cancer on 25 November 2007 and the following day, announced her retirement. |
| Kansas |
| Senator Samuel D. "Sam" Brownback | Republican | Senate Class 3 | Open Seat. 19 October 2007: Withdrew his candidacy for President and announced his retirement at the end of his term. |
| Governor Kathleen Sebelius | Democratic | Governor | Open Chair. Term Limit. At term limit |
| Louisiana |
| Governor Kathleen Babineaux Blanco | Democratic | Governor | Open Chair. Governor Blanco announced that she would not seek re-election on 20 March 2007. However, on 26 April 2007, she may consider re-entering. |
| Congressman Piyush "Bobby" Jindal | Republican | House CD 1 | Open Seat. Ran for and won the gubernatorial election in 2007. |
| Maine |
| Governor John Elias Baldacci | Democratic | Governor | Open Chair. Term Limit. At term limit |
| Congressman Thomas H. Allen | Democratic | House CD 1 | Open Seat. Candidate for Senate in 2008 |
| Michigan |
| Governor Jennifer M. Granholm | Democratic | Governor | Open Chair. Term Limit. At term limit |
| Minnesota |
| Congressman Jim Ramstad | Republican | House CD 3 | Open Seat. 17 September 2007: Announced that he will not seek re-election. |
| Mississippi |
| Congressman Roger F. Wicker | Republican | House CD 1 | Vacant Office. On 31 December 2007, Mississippi Governor Haley Barbour chose Congressman Roger Wicker to fill the vacant U.S. Senate Class 1 seat until the 4 November 2008 special election is held. |
| Congressman Charles W. "Chip" Pickering, Jr. | Republican | House CD 3 | Open Seat. On 16 August 2007, Congressman Pickering stated that he will not seek re-election in 2008. |
| Nebraska |
| Senator Charles T. "Chuck" Hagel | Republican | Senate Class 2 | Open Seat. Announced his retirement on 10 September 2007. |
| New Jersey |
| Congressman H. J. "Jim" Saxton | Republican | House CD 3 | Open Seat. Announced retirement 9 November 2007 |
| New Mexico |
| Senator Pete V. Domenici | Republican | Senate Class 2 | Open Seat. 4 October 2007: Announced retirement at the end of his current term. |
| Governor William B. "Bill" Richardson | Democratic | Governor | Open Chair. Term Limit. At term limit. Running for President in 2008. |
| Congressman Heather A. Wilson | Republican | House CD 1 | Open Seat. Running for the Class 2 Senate Seat in 2008. |
| Congressman Stevan E. "Steve" Pearce | Republican | House CD 2 | Open Seat. Running for the Class 2 Senate Seat in 2008 |
| New York |
| Congressman Michael R. McNulty | Democratic | House CD 21 | Open Seat. Announced retirement 29 October 2007 |
| North Carolina |
| Governor Mike Easley | Democratic | Governor | Open Chair. Term Limit. At term limit |
| Ohio |
| Congressman David Lee "Dave" Hobson | Republican | House CD 7 | Open Seat. Announced retirement 14 October 2007 |
| Congressman Deborah D. Pryce | Republican | House CD 15 | Open Seat. Announced retirment 16 August 2007 |
| Congressman Ralph S. Regula | Republican | House CD 16 | Open Seat. Announced retirement 12 October 2007 |
| Oklahoma |
| Governor Brad Henry | Democratic | Governor | Open Chair. Term Limit. At term limit |
| Oregon |
| Governor Theodore R. "Ted" Kulongoski | Democratic | Governor | Open Chair. Term Limit. At term limit |
| Pennsylvania |
| Governor Edward G. "Ed" Rendell | Democratic | Governor | Open Chair. Term Limit. At term limit |
| Rhode Island |
| Governor Donald L. Carcieri | Republican | Governor | Open Chair. Term Limit. At term limit |
| South Carolina |
| Governor Marshall C. "Mark" Sanford, Jr. | Republican | Governor | Open Chair. Term Limit. At term limit |
| Tennessee |
| Governor Philip N. "Phil" Bredesen | Democratic | Governor | Open Chair. Term Limit. At term limit |
| Texas |
| Senator Kay Bailey Hutchison | Republican | Senate Class 1 | Open Seat. 15 October 2007: Announced she would not seek re-election and may step down before the end of her current term. |
| Virginia |
| Senator John William Warner | Republican | Senate Class 2 | Open Seat. 31 August 2007: Announced retirement effective at the end of his current term. |
| Governor Timothy M. "Tim" Kaine | Democratic | Governor | Open Chair. Term Limit. At term limit |
| Wyoming |
| Governor Dave Freudenthal | Democratic | Governor | Open Chair. Term Limit. At term limit |