Sure it is possible but the cookies would have to crumble in just the right way for that to happen. ND's loss to NIU not only virtually killed ND's playoff chances but did major damage to A&M and Louisville's chances since neither are likely to win their respective conferences and another loss coming to an unimpressive ND team.
ND's chances are on fumes already and another loss would completely sniff those out. The harsh reality is that from the beginning this year, given the schedule's overall weakness, ND could only afford one loss to get in and it would have had to be against one of the "better" teams on the schedule. i.e., Texas A&M, USC or FSU. FSU bleak season to date pretty much eliminates one of the impressive wins we needed to get in with one loss.
A&M is wishing on a star to get in since, given the SEC, beating a good ND team was their ticket in assuming they are likely, at best, to be the 4th SEC (any realistic guessing at this point would point to Georgia, Alabama and Texas as almost givens) team in and that assumes they would only absorb one loss the rest of the season which is a flight of fancy.
Louisville's loss to ND as well almost kills their chances unless they can win the ACC and it is a dream to think that they can beat Clemson and Miami.
ND's way in is to go undefeated ( a major leap of faith) and hope that both Louisville and A&M are "in the conversation." Absent that, it is most probable that lal 3 teams are out and it would be NIU that killed all three teams' chances.