think it's pretty safe to say that 11 of the 12 playoff spots are essentially spoken for right now.

Historically speaking, all teams with 10+ wins out of the Big Ten and SEC have finished ranked high enough to get a playoff bid in the current format. Likewise, all teams with 11+ wins out of the ACC and Big 12 (and the PAC-12) have finished ranked high enough to get a playoff bid in the current format. G5 teams have only been ranked high enough to get an at-large bid when they have been undefeated.

Based on the above criteria, the following teams have essentially locked up playoff bids:

Big Ten: Oregon (12-0), Penn St. (11-1), Indiana (11-1), Ohio St. (10-2)

SEC: Texas (11-1), Georgia (10-2), Tennessee (10-2)

ACC: SMU (11-1)

Independents: Notre Dame (11-1)

To the above 9 teams, the winner of the Big 12 championship game (Iowa St. v. Arizona St.) and the MWC championship game (Boise St. v. UNLV) will also get a bid to the playoffs, leaving potentially 1 more bid for an at-large team.

If Clemson beats SMU to get the ACC auto-bid, then SMU will likely still get a spot which puts the field at 12 teams.  If SMU wins, then you have to start looking at teams that DON'T meet the above criteria. Loosening up the criteria by one game gives the following optionst:

SEC: Alabama (9-3), South Carolina (9-3), Ole Miss (9-3), Missouri (9-3)

Big Ten: Illinois (9-3)

Big 12: BYU (10-2), loser of B12 title game (10-3)

ACC: Miami (10-2)

G5: Army (11-1 if they win the AAC championship), Boise St. (11-2 if they lose the MWC championship)

If I were the one making the final selection, I would probably pick BYU. Even removing my own biases I think they have the strongest resume of the above group.  That being said, if I were putting money on who gets the final spot I would go all-in on a 3-loss SEC team getting the nod - with Alabama being the most likely team selected.  It is probably in BYU's best interest to have SMU blow out Clemson and Arizona St. blow out Iowa St. in dominant convincing wins. That may be enough to get BYU back in the conversation in the top 15. But they will probably end up with the 3-loss SEC trio of Alabama/South Carolina/Ole Miss ahead of them as well as a 2-loss Miami team.