Ezenwa made 3 of 6 from 3-point range and grabbed eight rebounds for Idaho State (5-15, 2-6 Big Sky), which shot 53 percent (8 of 15) from behind the arc. Jeffrey Solarin added 15 points.
Iziahiah Sweeney hit a jumper with 8:47 left, giving Portland State (10-8, 4-4) its biggest lead, 68-62. The Vikings trailed by as many as 10 in the second half.
Marcus Bradley made a jumper and Hansen hit a 3 to start a 14-2 run by the Bengals which gave them a 76-70 advantage with four minutes to play.
Portland State made just 2 of 8 field goals from there and Idaho State made 4 of 6 free throws to seal it.