Who left September in prime playoff position?

College football fans across the country seem certain -- absolutely positive -- their conference champion will finish in the College Football Playoff selection committee's top four. There's only one problem: The math doesn't add up. Five champs, four spots.

As we say so long to September, here's a look at how each of the Power 5 conferences stack up in the playoff picture, ranked from those in the best shape to the worst:

1. SEC

Lead CFP contender: Alabama (5-0). The Tide have looked dominant all month, outscoring their past four unranked opponents 207-33 and earning a respectable season-opening win against Florida State in spite of the Noles' 1-2 start. Alabama is one of the few teams in the country that seems to be a September lock for the CFP, but with the rest of the SEC appearing so weak, it's fair to question the Tide's strength of schedule. If the Tide are an undefeated SEC champ, though, it won't matter.

Best backup option: Georgia (5-0). The Bulldogs embarrassed Tennessee 41-0 on their home turf, asserting themselves as the only team in the SEC East to take seriously. (Sorry, Florida.) ESPN's Football Power Index projects Georgia to win each of its remaining games, with the exception of a road trip to Auburn on Nov. 11. Win the East, beat Bama in the SEC title game, and Georgia is in.

Sleeper: Auburn (4-1). The Tigers' only loss is on the road to the defending national champs, which is not exactly an eliminator. If Auburn can pull off the upset against Alabama in the Iron Bowl and win the SEC, it should be in.

Team that has fallen off the pace: LSU (3-2). Saturday's loss to Troy signaled bigger problems, and this could get ugly, as three of the Tigers' next four opponents are ranked.

2. ACC

Lead CFP contender: Clemson (5-0). The Tigers have arguably the most impressive playoff résumé to date, as they beat Auburn and earned two conference road wins against ranked opponents in Louisville and now Virginia Tech. According to FPI, Saturday's game in Blacksburg was Clemson's toughest remaining game, and it is favored to win out. Clemson and Bama seemed destined to meet again.

Best backup option: Virginia Tech (4-1). One loss to the defending national champs isn't the end of the Hokies' CFP hopes, especially because they could see Clemson again in the ACC championship game. Virginia Tech has no margin for error, though, and it needs to hope that Miami remains ranked by the time it visits the Canes on Nov. 4.

Sleeper: Miami (3-0). The Canes looked like Coastal contenders in Friday's win at Duke, but they have yet to earn a marquee win that legitimizes their playoff hopes.

Team that has fallen off the pace: Florida State (1-2). It started with the season-ending injury to starting quarterback Deondre Francois and continued with the effects from Hurricane Irma. The home loss to NC State knocked FSU out of the Top 25 and the CFP conversation.

3. Big 12

Lead CFP contender: Oklahoma (4-0). The Sooners have one of the best nonconference wins of the season, on the road against then-No. 2 Ohio State, and are favored by FPI to win each of their remaining games. If Oklahoma State, TCU and West Virginia can all stay ranked, that would give the Sooners the opportunity to have four regular-season wins against ranked opponents, plus a fifth in the Big 12 title game. They would be a no-brainer for the top four at that point.

Best backup option: TCU (4-0). The Horned Frogs earned a statement conference road win at Oklahoma State last week and have shown that their defense is good enough to contend for the Big 12 title. TCU is no stranger to the CFP's top four, but it has to beat the Sooners to get there again.

Sleeper: West Virginia (3-1). The Mountaineers' only loss so far has come to Virginia Tech. They have yet to beat a ranked opponent but will have a chance to upset TCU on Saturday.

Team that has fallen off the pace: Oklahoma State (4-1). After losing at home to TCU last week, the Cowboys have no margin for error, but if they win out and punctuate their résumé with a Big 12 title, they should be in.

4. Big Ten

Lead CFP contender: Penn State (5-0). The Nittany Lions have the front-runner for the Heisman Trophy in Saquon Barkley, and they earned a gritty conference road win at Iowa, but September strength of schedule is an issue. PSU has yet to beat a ranked opponent, and its nonconference opponents -- Akron, Pittsburgh and Georgia State -- have a combined record of 5-8. If PSU can win back-to-back games against Michigan (Oct. 21) and Ohio State (Oct. 28), though, last year's snub should be avenged.

Best backup option: Ohio State (4-1). If the Buckeyes' only loss is to likely eventual Big 12 champ Oklahoma, it won't keep them out of the top four. But they're under pressure to win out.

Sleepers: Wisconsin (4-0), Michigan (4-0). The Badgers have looked like the best in the West, but they have only one ranked opponent on their schedule: Michigan. The Wolverines, however, have struggled to find their offensive identity. Quarterback Wilton Speight suffered an injury last week at Purdue, and his status remains uncertain for Saturday's game against Michigan State.

Team that has fallen off the pace: None. The Big Ten's top teams are all still in contention.

5. Pac-12

Lead CFP contender: Washington (5-0). Even though Washington State just upended USC, giving the Cougars a better win than anything Washington has on its résumé, the Huskies still look like the more complete team with the better chance of sustaining success. As was the case last year, Washington doesn't have much margin for error because of a weak nonconference schedule that included Rutgers, Montana and Fresno State. Last season, there weren't any other one-loss Power 5 champions to challenge the Huskies or knock them out of the top four, as Penn State and Oklahoma each had two losses. If that's not the case this year, Washington probably would need to go undefeated to get in ahead of another Power 5 champ with a better résumé.

Best backup option: Washington State (5-0). The Cougars no doubt played themselves into the CFP conversation by beating USC on Friday night, but the challenge will be sustaining their success. While Washington is favored to win each of its remaining games, FPI gives Wazzu less than a 50 percent chance to beat Oregon, Stanford and Washington.

Sleeper: Utah (4-0). The Utes had a bye week to prepare for Stanford, but they need to win the next two games, against the Cardinal and at USC, to be taken seriously.

Team that has fallen off the pace: USC (4-1). The Trojans haven't looked the part of a CFP contender. Injuries to the offensive line haven't helped, and quarterback Sam Darnold has been inconsistent. USC is under pressure to win out, and it still has to face Notre Dame.