Max Yon scored 15 points and Marek Olesinksi added 14 for the Falcons (9-10, 3-5). Air Force played without leading scorer Tre' Coggins due to disciplinary reasons and lost its third straight and fifth in six games.
Elorriaga had all of his points in the first half and Bropleh tallied 11 as the Broncos held a 39-31 halftime lead. Boise State led by as many as 17 in the second half before Air Force cut its deficit to 65-55 on Yon's basket with 2:06 left.
Two free throws by Derrick Marks and a basket by Drmic helped the Broncos hold off the charge.
Boise State out-rebounded the Falcons 31-21 behind Watkins' fifth consecutive double-double and held a 16-0 edge in bench points.
Air Force's depth took a hit with Coggins sidelined and DeLovell Earls moved into the starting lineup but played just 18 minutes before fouling out. Coggins, who averages 17.4 points, also will miss Air Force's game at Nevada on Saturday.
Boise State had an eight-point halftime edge and quickly expanded the lead after the break. Drmic scored six points during an 8-0 surge to push the advantage to 49-34 with 16:46 remaining and two free throws by Watkins increased the margin to 17 with 11:14 to play.
Air Force moved within 61-50 on a basket by Kamryn Williams with 5:16 remaining before Watkins scored the Broncos' next four points to stretch the margin back out to 14 with 3:47 left.
The Falcons were hurt by 13-of-23 free-throw shooting and Yon committed five of their 10 turnovers. Justin Hammonds with 12 points and Williams with 11 also scored in double figures.
Drmic and Elorriaga each made three 3-pointers for the Broncos, who were 7-of-18 from behind the arc. Elorriaga's final 3-pointer was the 200th of his career, making him only the fourth Boise State player to reach that milestone.
Elorriaga scored 11 points and Bropleh added nine over the first 13 1/2 minutes as Boise State took a 26-15 advantage. Air Force battled back to within 34-31 on a dunk by Williams with 1:21 left before Elorriaga drove for a basket and Drmic drained a 3-pointer to give the Broncos a 39-31 halftime lead.