The influential Cook Political Report has moved the race for retiring Sen. Saxby Chambliss's U.S. Senate seat into the "tossup column."

Despite this year's overall grim outlook for Democratic chances in the Senate, the Report says :

These ratings change aren’t all bad for Democrats. The open seat in Georgia moves to the Toss Up column from Lean Republican. Michelle Nunn is proving to be perhaps the best Democratic challenger of the cycle. Republicans, meanwhile, are mired in a crowded primary that seems destined to produce a run off. As a result, Republicans won’t have a nominee until late July. Moreover, this may be the one race where the threat of nominating a candidate who is generally unelectable in a statewide general election is very real.

Longtime Savannah Congressman Jack Kingston is giving up his House of Representatives seat in order to run for the Senate seat, in a crowded field of Republicans.