Calhoun, a freshman who's No. 4 on Colorado's tailback depth chart, ran for 137 yards as the 13th-ranked Buffaloes defeated Nebraska 28-13 Friday for their first victory in Lincoln since 1990.
Fullback Brandon Drumm added two touchdowns for the Buffaloes (9-3, 7-1 Big 12), who clinched the North Division championship. They'll go to Houston for next Saturday's Big 12 championship game against Oklahoma having won eight of nine after a 1-2 start.
"We didn't want to share it," Colorado coach Gary Barnett said. "We wanted to win it in Lincoln, which is very difficult to do. We weren't fancy or pretty this season. We just played hard and found a way to get the job done."
Calhoun had all but one of his 20 carries in the second half while Bobby Purify sat out with a sore knee and sprained ankle. Purify had been filling in for Chris Brown, the nation's third-leading rusher, who was held out of the game because of a bruised sternum.
Barnett opted to go with Calhoun instead of third-stringer Marcus Houston once Purify left for good in the third quarter.
"I wasn't surprised," Calhoun said. "I knew Chris wouldn't be able to go, and I knew Bobby had an ailing knee, so I prepared myself all week to be the man to carry the ball."
The Cornhuskers (7-6, 3-5) ended their worst regular season since 1961, when they were 3-6-1. The Buffs denied the Huskers a chance to extend their unprecedented streak of nine-victory seasons to 34. Nebraska could have reached nine by winning Friday's game and a bowl.
"I'd be surprised if any teams ever makes a run at that," Nebraska free safety Philip Bland said of the streak.
The Huskers, who have lost four of their last six games, had a losing conference mark for the first time since 1968, when they went 3-4. They came back to go 9-2 overall the following season and won the national title in 1970 with an 11-0 record.
Nebraska's loss marked the first time since 1990 it had failed to beat a ranked opponent. That year, the ninth-ranked Buffs came to Lincoln and won 27-12.
Despite all their struggles, Nebraska still will get invited to a bowl, and the Huskers must win that game to stretch their streak of winning seasons to 41.
Calhoun led a Colorado rushing attack that generated 253 yards - 178 after halftime.
"They went in at halftime and said, `We're going to run the ball,"' Nebraska linebacker Scott Shanle said. "The first half, it surprised me they threw the ball so much. The second half, they didn't go away from their running game at all. They were getting 5 or 6 yards on first down."
After Dale Endorf's 49-yard field goal put Nebraska up 13-7 early in the third quarter, Colorado used consecutive scoring drives to take a 21-13 lead.
"The bottom line is that we were in the ballgame," Nebraska coach Frank Solich said, "but we didn't get the things done that needed to get done in order to make it work."
Purify finished a 15-play, 80-yard drive with a 2-yard run to give the Buffs a one-point lead. Then, after Calhoun busted loose for 35 yards to open Colorado's next series, Drumm bulled his way into the end zone from a yard out.
The Buffs sealed the victory late in the fourth quarter when Drumm broke a 16-yard touchdown run five plays after Nebraska I-back David Horne fumbled away the ball at the Huskers 30.
Endorf, a walk-on who replaced the suspended Josh Brown, made a 33-yard field goal late in the second quarter to give Nebraska a 10-7 halftime lead. Brown's suspension came after his arrest last week on suspicion of drunken driving.
Colorado opened the scoring in the first quarter after Buffs cornerback Phil Jackson intercepted Jammal Lord's pass at the Colorado 13. Seven plays later, Robert Hodge lofted a 40-yard touchdown pass to Derek McCoy.
The Huskers evened the score at 7-7 early in the second quarter when tight end Matt Herian beat free safety Medford Moorer to haul in an 80-yard TD pass from Lord.