Harris scored five straight points for the Wildcats (6-8, 1-1 Big Sky), giving Weber State a 67-62 lead with 1:42 left in the game. Davis scored the next six and the Wildcats hung on for the win.
Juan Pablo Silveira's 3-pointer with about 10 minutes left in the game gave the Wildcats a 54-43 lead, their biggest advantage of the game. The Vikings came back with an 11-1 run and later took a 62-61 lead on Jeremiah Dominguez's 3-pointer with 3:31 remaining.
Steve Panos, who scored 11, tied it again with a free throw and Harris put the Wildcats up for good with five straight points.
Weber State missed its first six shots and trailed 9-0 early in the game, however the Wildcats scored the next 11 points with Arturas Valeika capping off the run with a dunk.
The officials whistled Valeika for hanging on the rim too long and Portland State's Kyle Coston hit both free throws to tie the game. Neither team led by more than three points for the rest of the half until WSU ended the stanza on an 8-0 run to lead 34-29 at the break.