Tucker was just 1-for-6 in the first half, his only points from the field a 3-pointer that allowed Wisconsin (26-2, 12-1 Big Ten) to go into the half up 36-25. But he scored 12 of his 16 second-half points during a 22-6 run that broke open the game.
Tucker said his teammates kept pumping him up at halftime, urging him to get hot.
"They come to me and they always tell me to lead the team, and that's what I did," Tucker said. "I let everything slow down, and I started taking the shots that I wanted."
Kammron Taylor had 18 points, while freshman Jason Bohannon added a career-high 11 for Wisconsin.
The Nittany Lions (10-15, 1-11) hung around for the first few minutes of the second half and trailed 42-33 after Geary Claxton hit a jumper.
But then Tucker seemed to find his game, and the Badgers went on their big run, opening up a 64-39 lead.
Penn State struggled to take care of the ball, committing 18 turnovers, and the zone defense the Nittany Lions used much of the game backfired when the Badgers hit 12-of-23 from 3-point range.
Taylor was 4-of-6 from 3-point range, while Bohannon came off the bench to shoot 3-of-4 from behind the arc. After shooting 26 percent from 3-point range in the first eight Big Ten games, the Badgers are hitting 46 percent from behind the arc over their last five games.
"Offensively, they've got the whole package then," Penn State coach Ed DeChellis said. "It's a double-edged sword. You can try to take their inside away and then Taylor steps out and hits some shots and that kid Bohannon (hits a few). It makes them very, very hard to guard."
Claxton led Penn State (10-15, 1-11) with 15 points and six rebounds, while Jamelle Cornley added 12 points.
Penn State is in the middle of a brutal three-game stretch. The Nittany Lions hosted No. 2 Ohio State last Wednesday, losing 64-62, and travel to Columbus, Ohio, this coming Wednesday to play the Buckeyes again. Assuming the Buckeyes and Badgers remain ranked second and third, respectively, in the polls this week, it would be the first time a Big Ten team has played three straight games against opponents ranked in the top three, according to the school's research.
Wisconsin's 26th win of the season sets a school record with three games left in the regular season. It's the third time in four seasons the Badgers have won at least 25 games, the best stretch in school history.
Wisconsin finishes the Big Ten season at Michigan State, at Ohio State and then home against the Spartans again. Wisconsin went into Saturday tied with Ohio State atop the Big Ten conference. The Buckeyes play at Minnesota Sunday.
"Our destiny is on our own hands. I thrive off that. This will tell the tale of this Wisconsin team this year," Tucker said.
"Everything we do from here adds to our legacy. I'm accepting the challenge."