Ohio State has a crucial series this weekend with Northern Michigan. If OSU loses even one game, they stand a good chance at falling quite a few spots in the PWR (and falling below .500 on the year). OSU is currently at 13th in the PWR.
St Lawrence and Harvard have a critical game as well. SLU is at 14, Harvard at 12 in the PWR. The loser of that game will fall in the PWR.
Being that OSU, SLU, and Harvard are all directly in front of the Sioux in the PWR, they could move up a few spots just from the outcomes of those games. They need to take care of business against DU though first and foremost.
The Sioux are not sunk. They are within 2 PWR spots of making it right now, and there is still a maximum of 10 Sioux games remaining (before the NCAA tourney), so lots can/will change.