The thing is, that was probably the best team that FSU is going to play on the way in. The rest of their schedule is...
vs Virginia (4-4)
@ Miami (5-3)
vs Boston College (5-3)
vs Florida (3-3)
ACC Championship Game (probably against Duke (6-1))
FSU should have no issues at home against Virginia or Boston College. Florida and Miami are rivalry games, so anything is possible there. However, FSU will also likely be just as up for those rivalries, so it is difficult for me to see them ****ting the bed, especially at home against Florida if they have a shot at another perfect regular season.
That leaves the ACC Title game, and if the matchup is against Duke, then I really like FSU's chances of going undefeated. Duke just isn't the type of team to push FSU. If we look at the Seminole's close games (Clemson, Notre Dame, and Louisville), all of those teams play very good defense (and Winston was obviously out for the Clemson game). Duke might have good defensive numbers, but look at the competition. Plus, throw in the fact that FSU would have a shot at the playoffs, and I think FSU would cruise there.
Ultimately, I don't think they'll play another really close game the rest of the way until the playoff. Of course, I also don't think they will repeat either...at least I hope not.
It would be interesting though to see how far FSU would fall with a loss. My guess is they would drop to about 6 or 7. The rankings committee seems significantly more concerned with who you have beaten rather than who you lost to (see MSU and Notre Dame), and Florida State would still have wins over Oklahoma State, Clemson, Notre Dame, and Louisville. Those are better than either TCU (although if TCU wins out, that could change) or Michigan State. Throw in that the SEC West is going to beat up on each other, and it is entirely feasible for FSU to lose a game, and still make the playoff.