The Nuggets owned a tenuous 56-51 lead at halftime, but they started the third quarter on an 8-0 run.
Utah never seriously threatened over the game's final 20 minutes.
"I don't think my [halftime] speech had much to do with it," said coach George Karl. "I just think we were very good defensively in the second half."
The Jazz scored only 17 points on 6-for-18 shooting in the third quarter, when Denver took control of the game.
"In the first half," Karl said, "they scored a lot off our turnovers and I don't think we rebounded well. We made them miss a lot of shots, but they rebounded the ball and I don't think our defense had activity or aggressiveness."
That changed in the second half, which Utah opened with six straight missed shots, including five jumpers from 18 feet or beyond.
The win was Denver's 17th in the last 19 games and kept them in the middle of a race with Memphis and the L.A. Clippers for home-court advantage in the first round of the playoffs.
Meanwhile, Utah slipped one-half game behind the L.A. Lakers in the race for the eighth and final playoff berth in the Western Conference.
"It's a solid win for us in a race that is probably going to go down to the last week," Karl said. "In a way, I hate helping the Lakers. But now maybe they can help us. They have Memphis and the Clippers in the next two games."
Former University of Utah star Andre Miller, filling in as the starter for injured point guard Ty Lawson, finished with 13 points and six assists in 27 minutes against the Jazz.
Miller, who 15 years ago helped lead the Utes to the NCAA championship game, turned 37 on March 19.
"It was a big win, knowing that it was a tough road game and that Utah is fighting for a playoff spot," he said. "We came out and played good, solid basketball for 48 minutes."
No. 3 point guard Evan Fournier, who doesn't play much when Lawson is healthy, finished with 18 points and two assists in 21 minutes.
"Just stay ready and stay focused and play hard," Fournier said. "… I'm just enjoying it right now because I know, when Ty comes back, I may go back to the bench."
Lawson is sidelined with a torn plantar fascia in his right foot. It is not known when he will return.