The former chief of staff to retiring Rep. John Linder (R-Ga.) won the GOP primary runoff Tuesday, securing 55 percent of the vote.

Rob Woodall was declared the winner of the 7th district runoff by the Associated Press. He faced radio host Jody Hice, who come in second in the July primary. 

Hice, a former minister, stirred controversy during the race with a billboard campaign referencing President Obama. The billboards asked, "Had enough of Obama's change?" The “c” in the word change was replaced with a hammer and sickle. 

Linder officially endorsed Woodall in April. 

Support of the Fair Tax turned out to be a major issue in the primary, even though every one of the Republicans running voiced support for it. The candidates squabbled over who was the strongest backer of the tax proposal, which is based on consumption rather than income.

Linder co-authored a book on the Fair Tax with conservative radio host Neal Boortz.  

Woodall is expected to retain the seat in November.

--Shane D'Aprile contributed to this post.