2008 Senate race landscape

WASHINGTON (CNN) - New Mexico Sen. Pete Domenici’s decision not to seek a seventh term gives Republicans their fourth open Senate seat to defend in 2008.

Also retiring at the end of this term are GOP Sens. Wayne Allard of Colorado, John Warner of Virginia and Chuck Hagel of Nebraska. Sen. Larry Craig of Idaho, who had said he would resign his seat on September 30 after pleading guilty to a disorderly conduct charge, remains in office, his re-election plans unclear. No Democratic senators have indicated plans to retire.

A total of 34 U.S. Senate seats will be up for grabs next year, with Republicans defending 22 seats, compared to 12 seats for Democrats.

Here's a quick look at where things stand in the U.S. Senate for the 2008 election. 

Retiring senators:

* Sen. Wayne Allard, R-Colorado (announced 1/15/2007)

* Sen. John Warner, R-Virginia (announced 8/31/2007)

* Sen. Chuck Hagel, R-Nebraska (announced 9/10/2007)

* Sen. Pete Domenici, R-New Mexico (announced 10/3/2007)

SENATORS UP IN 2008

Alexander, Lamar R-TN

Allard, Wayne R-CO (OPEN SEAT)

Barrasso, John R-WY

Baucus, Max D-MT

Biden, Joe D-DE

Chambliss, Saxby R-GA

Cochran, Thad R-MS

Coleman, Norm R-MN

Collins, Susan R-ME

Cornyn, John R-TX

Craig, Larry E. R-ID*

Dole, Elizabeth R-NC

Domenici, Pete R-NM (OPEN SEAT)

Durbin, Richard D-IL

Enzi, Michael B. R-WY

Graham, Lindsey R-SC

Hagel, Chuck R-NE (OPEN SEAT)

Harkin, Tom D-IA

Inhofe, James M. R-OK

Johnson, Tim D-SD

Kerry, John F. D-MA

Landrieu, Mary L. D-LA

Lautenberg, Frank D-NJ

Levin, Carl D-MI

McConnell, Mitch R-KY

Pryor, Mark L. D-AR

Reed, Jack D-RI

Roberts, Pat R-KS

Rockefeller, Jay D-WV

Sessions, Jeff R-AL

Smith, Gordon R-OR

Stevens, Ted R-AK

Sununu, John E. R-NH

Warner, John R-VA (OPEN SEAT)

*Though Sen. Craig indicated he would resign on 9/30/2007, as of this date he is still in office, and his plans for 2008 are unclear.