Oklahoma has won the Big 12 and is a lock-in to the playoff.
Alabama will have no trouble beating Florida and being the SEC representative.
Either Iowa or Michigan State will win the Big 10 championship and join the playoff.
There's really only one slot left. Clemson doesn't look invincible and North Carolina is the toughest opponent they've faced all year. However, North Carolina winning wouldn't be enough to get them into the playoff, because of their weak strength of schedule up until this point.
If Clemson loses to North Carolina Ohio State would get back into the playoffs. As the defending national champions and with only one loss (a last second field goal defeat against a great Michigan State team), they look like a lot more exciting team to have in the playoffs than Clemson.
Likewise, if Alabama loses to Florida somehow, Ohio State is the perfect replacement team for that opened slot.
If Clemson wins that would be fine too. They're obviously a quality team and deserving of a chance for the title so long as they beat North Carolina. There's basically no controversy. We have a clear top 4 for the season and a clear runner-up who can be slotted in if there are any upsets of said top 4.
Oklahoma, Alabama (or Ohio State), Iowa or Michigan State, and Clemson (or Ohio State).
If both Alabama and Clemson lose, and Iowa loses to Michigan State, life is still easy -- Oklahoma, Iowa, Michigan State and Ohio State would all be in the playoffs as a group of four 1 loss teams. There's no need to rely on two loss teams like Stanford or a Clemson team that just lost to a really low ranking opponent. Just go Big 10 all the way. If Iowa beats Michigan State while Alabama and Clemson both lose, you would get Iowa, Ohio State, Oklahoma and Stanford (if it beats USC in the Pac 12 championship). If Stanford loses, then North Carolina may as well get its shot at the title as the ACC champion.
With all the conference championship games, college football is about to have its most fun weekend of the season. However, there is a big problem looming on the horizon. The bowl season requires 80 teams to fill up all the empty slots, and there aren't 80 eligible bowl teams. At best there's around 77. Which means three bowl teams will have to be selected with 5-7 losing records. Losing record teams in bowl season! O.O
Which losing record teams should be the lucky winners of a bowl ticket anyway? How about Nebraska? They have a lot of pageantry, fame, and football fans over there. The other two can be Kentucky and Missouri. 5-7 in the competitive SEC conference is more impressive than 5-7 anywhere else, so you can give these teams the benefit of the doubt. They'd probably be better than the majority of 6-6 teams around the country.