Ongwae, who was 6 of 8 from the floor, also pulled down 10 rebounds. Majok Deng scored 14 points, Nick Coppola made 13 and DeMondre Harvey had a career-high 12 points and 10 rebounds. Jamaal Samuel also scored 12 for the Warhawks (4-3).
The Warhawks led 42-30 at the half. Northwestern State closed the gap and took a 68-65 lead with 5:45 left when Zeek Woodley made two free throws, Jalan West nailed a 3 and Woodley made another 3. Louisiana-Monroe's Justin Roberson answered with a layup, Deng slammed home a dunk and followed with a layup to reclaim the lead 71-68 with 4:15 remaining.
Woodley had 28 points, West added 21 and DeVonte Hall chipped in 11 for Northwestern State (3-5).