It is also because the republicans stand for nothing.
There’s no compelling reason to vote unless the democrat is an unacceptable lefty and Nunn reminds voters in Georgia of her conservative father.
Nunn is low key and does not drive enough republicans to the polls to vote against her. With the republicans standing for nothing, there’s no reason to turn out the conservative grass roots to get behind Perdue.
Sam Nunn was about as far from conservative as you can get without getting a hammer and sickle tattoo