Given how soft the bubble is, I'd like our chances with two more wins. At 19-13, I think odds are we'd be in if the first game loss in the BTT is to another tournament team.
19-13 with a loss to Penn State, Rutgers, etc., though, could be a bit stickier.
Beat NW, MN, and one of Ill/Purdue/MSU/OSU and I think we're comfortably in.