FILE - This May 20, 2014, file photo shows Democratic candidate for U.S. Senate, Michelle Nunn in Atlanta as she speaks to her supporters after her primary win was announced at an election-night watch party. Minutes after David Perdue won his Republican Senate primary in Georgia, a grainy image of Nunn was on Atlanta TV as a faceless voice slammed her as a rubber stamp for President Barack Obama. In turn, Democrats portray Perdue as a greedy executive who laid off workers. It’s all a clear indicator of what the next three months hold for a first-time Democratic candidate who may be the party's only hope for picking off a GOP-held Senate seat in November. (AP Photos/Akili-Casundria Ramsess, File)