LITTLE ROCK — The state Democratic Party filed a lawsuit Friday challenging the legality and authenticity of signatures gathered to place Ralph Nader on the presidential election ballot in Arkansas. The suit was filed in Pulaski County Circuit Court, a week after the secretary of state's office officially confirmed Nader's place on the ballot. Judge Timothy Fox is to hear arguments in the case Tuesday morning. The lawsuit charges widespread fraud and other irregularities in the petitions submitted to place the noted consumer activist on the Nov. 2 general election ballot. It claims more than 300 signatures on the...