Terrell Newby ran for 69 yards and a touchdown . Moore had 72 yards receiving, and Nebraska finished with 556 yards in all.
Thorson threw for 249 yards and had a 42-yard touchdown run. But he also threw two interceptions and was sacked four times, bringing his Big Ten-leading total to 15.
Austin Carr had another big game for Northwestern with 109 yards receiving and a touchdown, giving him at least one scoring catch in three straight games. But a team that seemed to be getting on track with last week's win over Duke after opening with losses to Western Michigan and Illinois State came up short against the resurgent Cornhuskers.
"These guys better figure it out pretty quick," coach Pat Fitzgerald said. "They better walk out of the locker room. They better hug whoever they love. They'd better go to bed and they'd better wake up and they've got to get ready to get their rear ends coached off this week because that's what's gonna happen. I'm not gonna sit here and I'm not gonna take it and I'm not gonna accept it. They'd better buckle it up. They'd better start hydrating right now because it's not acceptable the way we're playing.
"It starts and ends with me so I'm gonna fix it."
Nebraska drove 80 yards for a touchdown after Williams picked off Thorson in the end zone on the opening drive of the second half, with Carter's 4-yard TD catch making it 17-7.
Northwestern answered with a 24-yard TD pass from Thorson to Carr, but Jack Mitchell's extra-point attempt hit the left upright. The Cornhuskers then went 79 yards with Jordan Westerkamp running it in from the 10 to boost the lead to 24-13.
NEBRASKA: The Cornhuskers ultimately took charge after those early turnovers and continue to roll along in their second season under Mike Riley. It's a big improvement over last year, when they had to rally to finish 6-7.
NORTHWESTERN: Coach Pat Fitzgerald has been criticizing his team for not finishing drives. He'll probably have more to say about it, considering Northwestern racked up 388 yards. But the defense had its difficulties, too.
Nebraska might have put this one away in the first half if not for the turnovers.
On the game's opening possession, Newby fumbled as he tried to lung across the goal line at the end of a 49-yard run with two defenders in pursuit. The ball popped out as he contorted himself in mid-air along the sideline and bounced through the end zone.
Nebraska had the ball on the 2 late in the second quarter when a spinning Devine Ozigbo lost a fumble.
Nebraska certainly appeared to strengthen its standing in the poll with this win, taking control after a shaky first half.
While Fitzgerald said Jack Mitchell will continue to handle kickoffs, field-goal duties and extra points are now up for grabs. Mitchell will be competing this week with Matt Micucci after he booted a 27-yard field goal wide right and hit the upright on a missed PAT.
NEBRASKA: The Cornhuskers return home to face Illinois, which handed them one of their most disappointing losses a year ago. That was on a last-second touchdown and extra point in Champaign.
NORTHWESTERN: Northwestern goes on the road for the first time when it visits Iowa - a 14-7 winner at Rutgers after a surprising loss to North Dakota State.