The present invention is directed to a curable electrodepositable coating composition having a resinous phase dispersed in an aqueous medium. The resinous phase includes (a) one or more ungelled, active hydrogen-containing cationic salt group-containing resins which are electrodepositable on a cathode; (b) one or more at least partially blocked polyisocyanate curing agents; (c) at least one substantially non-volatile antioxidant; and (d) at least one volatile antioxidant. The present invention also provides a process for electrodeposition using the coating and substrates coated therewith.