Perdue, the former Dollar General CEO, said that "there's a high school graduate in this race, OK? I'm sorry but these issues are so much broader, so complex" as he talked about the economy and the federal deficit during a January meeting captured on video.
Appearing at a county women's group, Palin was expected to defend Handel, a former secretary of state who talked about her lack of college degree during her 2010 run governor.
Handel's campaign manager called Perdue's comments demeaning and said Handel has shown "great perseverance and sheer will" in overcoming the challenges of her youth. Palin endorsed Handel last week, and Handel's campaign said it has raised more than $100,000 since then.
At the same time, Nunn released her first campaign ad, "Optimist," which touts her work with the Points of Light Foundation. In the spot, Nunn mentions Republican President George H.W. Bush by name, a reflection of the Democrats' challenge to appeal to the state's conservative tilt.
Georgia's crowded primary is May 20, with Handel one of seven GOP candidates and Nunn one of four Democrats seeking the parties' nominations.
This is Palin's second endorsement of Handel; the first came during Handel's unsuccessful 2010 bid for governor.
Besides Perdue and Handel, the GOP field includes Reps. Paul Broun, Phil Gingrey and Jack Kingston, as well as Art Gardner and Derrick Grayson.
On the Democratic side, Nunn is competing against Democrats Steen Miles, Branko "Rad" Radulovacki and Todd Anthony Robinson.
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