The Bison (2-2) shot 58.5 percent from the field and used an early 9-0 run fueled by two 3-pointers from TrayVonn Wright and a triple from Braun to propel into the lead for good as they led 40-31 at halftime.
Western Michigan (3-2) trailed by double digits for most of the second half before cutting the lead to nine on a David Brown layup. North Dakota State sank their next eight free throws to close the game. Brown finished with 27 points for the Broncos, and Shayne Whittington and Connar Taya each had 16.
Braun was 3 of 6 beyond the arc and grabbed a team-high six rebounds. He was one of four Bison players to score in double figures as Wright had 16 and Lawrence Alexander added 10.
Colorado State graduate transfer John Gillon has chosen Syracuse, giving the Orange a potential starter at point guard entering the 2016-17 season.
DeSean Murray, who averaged 20.2 points as a sophomore at Presbyterian, will transfer to Auburn to play for coach Bruce Pearl.
Former Kentucky guard Ed Davender, the only Wildcat with at least 1,500 points and 400 assists, has died. He was 49.