It might not look likely, but some of what has happened this season ain't been likely either.
USC's loss is by 1 point at Utah. That's not exactly shameful. If they can put some convincing wins up against UCLA & Notre Dame, and then win the PAC championship over Utah (providing they beat Oregon next weekend).
If UoM vs OSU is a runaway one way or the other, that could eliminate one team there.
Plus, remember, numerous pundits here have forecasted TCU to lose multiple games yet, so that's going to happen as planned, right? I think the first one was supposed to be last night. Oh, wait......, ooooops.
The top 4 this week will be Georgia at 1 and then some combination of Michigan, Ohio State, and TCU to fill out 2 through 4 in some order. Tennessee and USC lurk in some order of 5/6. The only thing that we know for sure is that Michigan at OSU will be a result to possibly shuffle things around assuming they both win next weekend.