The Cougars (7-3) broke the game open in the second half with a 14-3 run that ended at 53-38. Washington State led for most of the first half and by six at halftime.
Daniels and Flynn were a combined 6 of 11 from 3-point range. Jeff Pollard added 12 points in 17 minutes off the bench, and Robert Franks, who is the leading scorer averaging 19.2 points, had 10 points to go with eight rebounds.
Drick Bernstine had nine points, 13 rebounds, five assists and three blocks.
"It is all about me playing with energy honestly," said Bernstine. "Blocks get these guys running. They get the whole team up and excited, it gets the fans into the game, I mean we didn't have a high attendance today, but it was pretty loud honestly. When you make energy plays it gets everybody involved, it gets everybody hyped up to do what they do. I just got to bring all the energy I can, that's what I do."
Ron Patterson had 19 points for IUPUI (2-7). Patterson hit three consecutive 3s in the first half after the Jaguars started the game 0 for 10 from 3-point range.
The Jaguars led for 18 seconds the entire game and could not get back in the game after the 14-3 run from WSU.
Washington State coach Ernie Kent credited a mid-week effort to speed up the game.
"On Wednesday, I tweaked my offense because I am kind of tired of seeing us play so slow," said Kent. "I have always wanted to play as fast as my teams have played in the past, and the one guy that gets us that way is Drick. He is the fastest guy with the ball."
Washington State snapped a three-game losing streak with two of those three losses coming on the road.
It was the first-ever meeting between the schools.
IUPUI: The Jaguars are reeling after their fifth straight loss.
Washington State: After losing three in a row, the Cougars get a needed win at home.
STAT OF THE NIGHT
The Cougars rank third nationally in made 3-pointers at 12.1 per game. WSU made eight 3-pointers for the game, but got the job done inside scoring 36 points in the paint to the Jaguars' 22.
IUPUI: The Jaguars face a powerhouse opponent in No. 12 Gonzaga on Monday for their final game of a three-game road trip.
Washington State: The Cougars prepare for a showdown in Spokane, Washington, against Kansas State on Wednesday.
The cream of the crop of American high school basketball will congregate in Colorado Springs from Oct. 5-7, as USA Basketball unveils its newly expanded Junior National Team minicamp in collaboration with the NBA, NCAA and NBPA.
Missouri guard Cullen VanLeer is retiring from basketball after tearing his ACL in the Tigers' final regular-season game last season.
For some teams, a win in the NCAA tournament would be a significant achievement. For the elite contenders, anything short of a Final Four run would be a disappointment.