Robert Turbin also ran for 109 yards, his fourth-consecutive 100-plus yard game for the Aggies (2-3). Turbin scored on the ground and caught a 19-yard Keeton pass for a score, becoming the Aggies' fourth all-time leading career scorer.
Wyoming (3-2) was led by Brett Smith, who threw for 265 yards on 28-of-46 attempts and an interception. Wyoming was held scoreless in the second half.
Keeton converted seven of seven third-down conversion attempts and USU never punted before the freshman was replaced with 4:05 remaining in the third quarter. He was 15-of-20 attempts and ran for 44 yards.
Utah State entered the game ranked 11th nationally in rushing, and ended the game with 318 yards on the ground and 548 total yards. The Aggies had 29 first downs in the game, their highest total of the season.
In the first half, Wyoming scored twice before USU's offense touched the ball. The Cowboys scored on their first possession, going 77 yards in seven plays, Brett Smith scoring on a short dive. USU's Kerwin Williams mishandled the ensuing kickoff and Wyoming jumped on the ball in the end zone for a 12-0 early lead.
The Aggies countered by scoring twice in the first quarter, the second one coming when Michael Smith scored on a 53-yard screen pass.
The first play of the second quarter was a 19-yard scoring pass to Turbin from Keeton, giving Utah State a 21-12 edge. The Aggies would score three more times in the second quarter and led 42-19 at halftime, the most points an Aggie team has scored in a half since 1991. Each of Keeton's scoring passes went to a different receiver. That list also included D.J. Tialavea, Tarren Lloyd and Stanley Morrison.
Utah State's final score, 4-yard run by Robert Marshall, gave the Aggies their highest point total since 1963.
The Aggies' return game also hit a season high, with Kerwynn Williams gaining 125 yards in kickoff returns (including one for 54 yards) and a 19-yard average in punt returns.
Ohio State remained No. 1 in the AP Top 25 and tied a poll record Sunday despite lagging support from voters. Meanwhile, No. 2 TCU and No. 3 Baylor edged forward and No. 4 Michigan State slipped.
Will Grier threw four touchdown passes to four receivers -- all in the first half -- and No. 25 Florida downed third-ranked Mississippi 38-10 on Saturday night.
Leonard Fournette highlighted his SEC-record third straight 200-yard game with a 75-yard touchdown run, and No. 9 LSU overcame Eastern Michigan 44-22 on Saturday night.
An officiating error led to an Oklahoma State touchdown Saturday in the Cowboys' 36-34 win over Kansas State.
Texas A&M receiver Ricky Seals-Jones, who was ejected for targeting midway in the second quarter of Saturday's game, took to Twitter late in the game, retweeting a tweet that questioned the call.
As if things weren't going bad enough at Texas, the Longhorns appear to have players on Twitter during lopsided losses and jabs at their coach accidentally being sent from other nearby teams.