Lander hit 8 of 10 free throws and went over 20 points for the fourth time this season, leading all scorers with 21 for the Leathernecks (5-4). Houpt made two 3-pointers among his 18 points.
The victory was the 250th of coach Jim Molinari's career.
Steven Crawford scored 10 points to pace the NAIA Wildcats (0-8), who counted the game as an exhibition.
Tommie Tyler's 3-pointer put Western Illinois ahead 18-6 with 12:31 left in the first half. Culver-Stockton ran off the next nine points to close within 18-15, but that was as close as the score got the rest of the way.
The Leathernecks led 27-21 at intermission and pulled away from there.