The Jayhawks (20-4, 9-2 Big 12) hit 11 of 20 on 3s, with Selden going 4 of 7. Kansas reached the 20-win mark for the 26th straight season.
Kansas sped up play in the second half and the Red Raiders couldn't keep pace. Perry Ellis scored 14 points, and Frank Mason III, Brannen Greene and Cliff Alexander each added 10 in the win.
Norense Odiase scored 13 points and Devaughtah Williams added 11 for the Red Raiders (12-13, 2-10).