A water-soluble cationic copolymer comprising the reaction product of (I) and a cationic quaternary amine having formula (a), wherein Y is (b) and n is 1 to 5; R?1, R2, R3¿ are independently H or C¿1? to C3 alkyl, R?4, R5 and R6¿ are independently C¿1? to C3 alkyl, X is a halide, hydroxyl or C1-C3 alkylsulfate anion. A second water-solulble cationic copolymer having general formula (II), wherein Z represents (c), or residual groups of -CH2N?O(R4R5)CH¿2CH=CH2X-, or mixtures thereof, and n is 1 to 5; R?1, R2 and R3¿ are independently selected from the group consisting of H or C¿1? to C3 alkyl; R?4, R5 and R6¿ are independently C¿1? to C3 alkyl, and X is a halide, hydroxyl or alkylsulfate anion; and wherein x, y and q represent molar percents of monomeric units in the copolymer such that q is 1 to 99 mol %, and the molar ratio of x to y is from 0 to 10. The copolymers of this invention are useful as flocculating agents and as drainage/retention aids in pulp and papermaking operations.