Whoever emerges in the final spot will be a prohibitive underdog against the top seed.

The 13 members of the selection committee will convene next weekend in Grapevine, Texas, to watch the conference championship games together, making the final assessments of each team’s closing argument. The committee has the former football coaches R.C. Slocum, Frank Beamer and Ken Hatfield and the Hall of Fame player Ronnie Lott. It also includes a former sportswriter, Paola Boivin. The rest of the committee is composed of a university president, a former Army chief of staff and six athletic directors, including the chairman, Rob Mullens of Oregon.

Thus far, the committee has seemed interested in igniting debate.

In its initial rankings, Clemson was placed fifth — one spot behind Penn State, which was also undefeated but less dominant. It was a provocative move, slotting an unbeaten defending champion outside the top four, but it came with a fail-safe: Penn State would be playing at Ohio State, so Clemson would be assured of leapfrogging someone. (And the issue became moot when Penn State lost at Minnesota on the Saturday after the first ranking.)

Two weeks ago, Baylor beat Texas, 24-10, and leapt past Wisconsin and Michigan, which won decisively, and an idle Florida to move from 14th to ninth.

There were other broad swings in Tuesday’s playoff ranking: Alabama fell seven places after a 48-45 loss to Auburn that was sealed on a missed field goal; Wisconsin, which has two losses, vaulted four spots after beating Minnesota, which almost inexplicably fell 10 places after that loss.

The writers’ and coaches’ polls have been far more stable.

L.S.U. jumped past Ohio State, almost unanimously voted into the top spot after it won convincingly at Alabama and, though the margin has narrowed some, the Tigers have maintained a considerable lead.

Asked on a conference call Tuesday night what the committee saw that the polls did not, Mullens said that Ohio State had four wins over Top 25 teams and that L.S.U. had three, though the Tigers’ wins were against better teams. “As we’ve talked in past weeks, both really have dynamic offenses, both have good defenses,” Mullens said. “Ohio State’s is just a little ahead at this point.”