The Huskies end Notre Dame's 16-game home winning streak.
Gordon scored nine points in the final 8 1/2 minutes to help hold off the Fighting Irish, who got as close as four points down the stretch after trailing, 46-31, at halftime.
"The first thing I said when I went into the locker room at halftime was, 'They're going to make a run, they're a good team, so everybody just keep the composure,'" Gordon said.
After Matt Carroll's layup sliced the deficit to 77-73 with 3:55 to go, freshman Marcus White had a tip-in and Okafor sank a short jumper to give the Huskies (18-6, 9-4, Big East East) an 81-73 advantage with 2:46 remaining.
Notre Dame (21-6, 9-4 West) got no closer than five thereafter.
Anderson matched his career high with 22 points. He scored 15 coming off the bench in the first half.
"I just came out ready to play, like I always do," said Anderson, who shot 5-of-7 from behind the arc in the first half. "I come out ready to play every game, that's my mentality."
The 6-9 Okafor, who blocked nine shots against St. John's on Saturday, collected 19 points, 10 rebounds and six blocks.
"They made a real good run, but we just kept our poise, kept cool, and pulled off the win," said Okafor. "People are going to try and test you. I haven't failed a test in awhile."
The win boosts the Huskies' lead in the conference's East division to a full game over second-place Villanova.
Carroll finished with 28 points and point guard Chris Thomas 19 for the Fighting Irish, who fell out of a first-place tie in the West division with the loss.
"They played a great game, they hit big shot after big shot, especially in the first half," Carroll said. "They had an answer for everything."