Sellers had all his points during Wyoming's 17-4 run to stretch the Cowboys' lead to 33-15 with 4:03 left in the first half. Alexander Aka Gorski hit a 3-pointer to make it a 20-point lead, 55-25 with 8:30 left.
Wyoming (8-1) rebounded after having its seven-game winning streak snapped against SMU on Friday.
Sellers shot 6 of 9 from the floor and grabbed four rebounds. Aka Gorski added nine points on 4-of-9 shooting. Alan Herndon grabbed 10 boards and chipped in seven points for Wyoming, which finished 28 of 52 from the field for 53.8 percent.
Billy Hansen scored 10 points and Brett Hartshorne added eight for Regis. Miikka Luosmaa had six rebounds for the Rangers.