snipped from http://sports.espn.go.com/ncf/news/s...roadtobcs/1202
Battle for No. 4
Just as controversial as the battle for the top two spots could be the battle for the final at-large spot into the Bowl Championship Series between California and Texas. Because Utah will finish in the top 6 of the standings, there is only one spot available for a team that did not win its conference le, and that will go to the highest-ranked team that is not a champion. If none of the three undefeateds lose on Saturday, that race is clearly between the Golden Bears and Longhorns.
Right now, Cal is way ahead of Texas in the polls, and Texas is even further ahead of Cal in the computers. If this weekend's games cause any change to those computer ratings, it would be very slightly in favor of the Bears, but more than likely the ratings for both teams will stay the same on Sunday.
If the computers do indeed hold steady, as few as three voters moving Texas ahead of Cal could give the BCS spot to the Longhorns. If exactly two AP voters and one coach switch their order in UT's favor, there will be a tie for No. 4 in the BCS. If two coaches and one AP voter make that same change, Texas would move in front. Ballots of coaches hold slightly more weight in the BCS formula because there are fewer total voters. (A tie, by the way, would allow the bowl with first selection to have its choice between the teams. Given that the Rose Bowl is likely to have first choice, Cal would win in the event of a tie).
Other than lose on Saturday, the worst thing the Bears could do is not look dominant against Southern Miss and give voters any reason to doubt their strength. A narrow victory could be fatal for Rose Bowl dreams. But even if Cal wins impressively, it won't be safe to assume the Bears have squelched any chance of the Longhorns making up ground in the polls.
Because this is the final week of the season, and relatively few teams are still playing, many coaches and writers might have had more time than ever to truly evaluate each team. It's possible that upon reviewing the résumés more closely, a few voters could decide to move some teams around. It's also possible that a few coaches had been letting someone else fill out their ballots up until this point and, upon taking those ballots back into their own hands, might decide to switch the order someone else created.
Having small shifts of points between top teams from the second-to-last poll to the last is fairly common, even when neither team is in action on the final day of the season. If Cal wins big, and Texas still makes up ground in the polls, some will suggest a conspiracy was in effect, but that wouldn't necessarily be the case. And if the movement takes place in the coaches' poll, the leading conspiracy theory will be brotherly love.
You see, Texas coach Mack Brown and Cal coach Jeff Tedford both vote in the coaches' poll, as does Brown's older brother Watson, the coach at UAB. And even though there are many other voters in that poll, the Brown brothers would be guilty until proven innocent in the minds of many angry fans. And because the American Football Coaches Association refuses to let USA Today reveal how each coach voted, innocence would never be proven.