Class resentment, not antisemitism, originally focused the crowd on Leo Frank

Evidence

Leo Frank, the son of a wealthy New York merchant, managed an Atlanta pencil factory which employed female labor at low wages. When one of the factory girls, Mary Phagan, was found murdered on the premises, unsubstantiated rumors of sexual perversion helped to fix suspicion on Frank. Most aroused were the working classes, who saw in Frank a symbol of the northern capitalist exploiting southern womanhood. — John Higham, Strangers in the Land, 1097