The Hawkeyes (7-0) took the lead on a 10-yard touchdown run by Adam Robinson early in the fourth quarter and their defense did the rest, holding the Badgers scoreless in the second half.

Stanzi was 17 of 23 for 218 yards and a touchdown, Derrell Johnson-Koulianos caught eight passes for 113 yards and cornerback Amari Spievey had two interceptions.

With Ohio State's loss to Purdue, the Hawkeyes (3-0 Big Ten) now are in the driver's seat for the conference championship and a BCS bowl berth. They've shown plenty of poise on the road along the way, having rallied from a 10-0 deficit at Penn State earlier this season.

Iowa coach Kirk Ferentz also said his team was dealing with the flu this week, although he didn't discuss specifics.

"It's reflective of our team," Ferentz said. "We keep pushing forward."

Meanwhile, Wisconsin (5-2, 2-2) squandered a chance to make some noise in the Big Ten title race. Facing a fairly soft schedule the remainder of the season, a win Saturday might have made the Badgers a surprise contender.

Instead they're left wondering what has happened to their offense, which looked surprisingly strong early on but now has wilted against back-to-back ranked opponents.

"We have an opportunity to come back home here against Purdue and see exactly where we are going to finish in this league," Badgers coach Bret Bielema said. "Early indications are that these guys are going to battle back."

The Badgers have managed only one offensive touchdown in their last two games, Montee Ball's 10-yard run in the second quarter Saturday; their lone touchdown in a loss to Ohio State last week came off a fake field goal.

Scott Tolzien, whose production in the passing game was a decisive factor in Wisconsin's 5-0 start to the season, was held to 143 yards passing and threw three interceptions against Iowa.

"I take it all on myself," Tolzien said. "The protection was good and it was bonehead decisions on my part."

Wisconsin began the game by tearing holes in Iowa's defense, with John Clay running for 58 yards on 10 carries in the first quarter. But Clay hurt his leg in the second quarter and didn't seem to be the same runner the rest of the game. He finished with 75 yards rushing.

Down 10-3 at the half, Spievey picked off a pass from Tolzien near midfield. Iowa drove to the Wisconsin 24, where Stanzi faced a third-and-7. Under heavy pressure, Stanzi rolled out and heaved deep to Moeaki, who made a tough catch in the corner of the end zone for a touchdown.

"Spievey picks it off and boom, we're in the end zone," Ferentz said. "We needed something positive to happen at that point."

Stanzi then was sacked and fumbled deep in his own territory on the Hawkeyes' next possession, but the Badgers' offense stalled and Wisconsin kicker Philip Welch missed a 38-yard field goal attempt.

That allowed Iowa to take control with a seven-play, 79-yard drive that ended with Robinson's go-ahead touchdown run -- a reward for Ferentz, who stuck with the run despite watching his team gain only 23 yards rushing in the first half.

Then Moeaki made another big play midway through the fourth quarter, a tough catch in traffic to convert a third-and-13 play despite being interfered with. The catch set up a career-long 48-yard field goal by Daniel Murray.

"It's extremely frustrating for us to play so well in the first half and come out in the second half and do what we did," Wisconsin defensive end J.J. Watt said.

Tolzien threw two interceptions in the final five minutes, one to linebacker A.J. Edds and the other to Spievey.

Iowa keeps the Heartland Trophy -- a bronze bull statue -- and takes a 42-41-2 lead in what had been a deadlocked all-time series between the two conference rivals.