An additive for cationic electrodepositable coating compositions is disclosed which improves hiding ability, stability, rheology and oil spot resistance. The additive is present in amounts of between 0.5 to 40 weight percent and is prepared by polymerizing in aqueous medium, under free radically initiated conditions, an aqueous dispersion of a polymerizable, ethylenically unsaturated monomer composition in the presence of a cationic polymeric surface active substance. The coating composition additionally has between 60 to 99.5 weight percent of a cationic salt group containing film forming polymer. Also disclosed is a method for coating which includes electrodepositing the above composition on an electrically conductive cathode.