Forte, a Georgia graduate transfer, made 12 of 18 shots in picking up his fourth double-double this season. Bryce White tied his career high with 20 points. Calaen Robinson had seven assists and made five steals.
The Vikings (6-8, 2-1 Big Sky) were only 3 of 15 from 3-point range, but 28 of 49 otherwise and outscored the Bobcats 42-22 in the paint.
Tyler Hall made four 3-pointers and scored 24 points for the Bobcats (7-9, 2-2).
Trailing by 15 with 9:13 to go, Montana State went on an 18-2 run for its first lead with 4:37 remaining. But White scored five points in a 9-2 stretch and the Vikings went up 72-66 with 41 seconds left. Zach Gengler then kept the Bobcats at bay with five free throws.