The win keeps the Longhorns (10-1, 7-1) alone atop the Big 12 standings and moves them closer to the conference championship game.
Ewers completed 23 of 33 passes and C.J. Baxter rushed for 117 yards, helping Texas extend its winning streak to five after an Oct. 7 loss to Oklahoma.
Rocco Becht threw for 323 yards and two touchdowns for Iowa State (6-5, 5-3), but the Cyclones netted only 9 yards rushing and averaged less than a half-yard per carry.
Quinn Ewers connects with Jordan Whittington for a 23-yard touchdown, extending Texas’ lead over Iowa State
Iowa State pulled within 13-9 when Becht threw a 14-yard touchdown to Eli Sanders, but the Longhorns’ T’Vondre Sweat blocked the extra-point kick and Austin Jordan ran it back 82 yards for two points and a 15-9 advantage.
Jerrin Thompson then intercepted Becht at the Texas 40-yard line to set up Ewers’ TD pass to Helm.
The Cyclones answered with a 66-yard touchdown pass from Becht to Easton Dean, trimming the margin to 23-16.
Bret Auburn’s 42-yard field goal for Texas made it a 10-point game with 6:10 left and extended his streak of makes to 14.
The Longhorns probably won’t move up because every team ahead of them won Saturday. Texas has been ranked No. 7 the past four weeks after peaking at No. 3.
Reporting by The Associated Press.
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