When Republican Saxby Chambliss announced last year that he would not seek a third term in the U.S. Senate, a long list of GOP candidates began lining up to succeed him. Now, David Perdue carries the party’s mantle into a November election that could be among the most competitive races in recent Georgia history. Perdue squares off against Democrat Michelle Nunn, daughter of former U.S. Sen. Sam Nunn, and Libertarian Amanda Swafford, a former Flowery Branch city councilwoman.