Jordan Shipley returned a punt for a touchdown in the fourth quarter for the Longhorns (5-0, 2-0 Big 12), who can now look ahead to next weekend's showdown with No. 19 Oklahoma.
Colorado (1-4, 0-1) led 14-3 behind tough defense and two first-half touchdown passes by Cody Hawkins that quieted the home crowd and even drew some boos.
Shipley caught a 39-yard TD with 46 seconds left in the first half and Wells' touchdown on the punt block by Marquise Goodwin put Texas up 17-14 in the third before Thomas' interception return.
