John Linder's sudden retirement has put his 7th Congressional seat up for grabs. 

Since yesterday, one potential candidate is out -- and one may be in. 

State senator David Shafer (R-Duluth) announced this morning he is not running for the now open congressional seat, preferring to remain in the Ga. General Assembly. 

"I will be doing everything in my power to help elect a strong, principled conservative to succeed John Linder in Congress. But I have determined that my public service is best performed here in Georgia, on the state level, near the ones I love," Shafer said today in a statement to the press. 

Another state senator, Don Balfour (R-Snellville) formally announced last night that he is a candidate for the Gwinnett County dominated district. Ralph Reed, who lost a state-wide primary for lieutenant governor to Casey Cagle in 2006, is considering re-launching his political career with a run as well. 

Now another top-tier contender has emerged: Col. Michael D. Steele, of "Black Hawk Down" fame. Sources close to the decorated war hero say he is seriously considering throwing his hat in the ring. Steele is a University of Georgia graduate who played offensive line for the 1980 national championship Bull Dogs. Steele blocked for Herschel Walker -- now Walker may be tackling fundraising chores for Steele if he gets in the race. Steele is a formidable speaker with a huge network of veteran support. A shorter primary window may favor his upstart candidacy. If Steele gets in, he'll likely win the July 20 GOP primary.