Twenty-five teams remain undefeated heading into the fifth week of the college football season. While teams such as Alabama, Ohio State and Boise State continue to dominate the national headlines, others are lurking just outside of the Top 25. Will one of these unbeaten dark horses creep into BCS Bowl contention? Which squad has the best chance to be this year's Cincinnati? Here's a look at the contenders.

The Cowboys may have found their next Dez Bryant in sophomore Justin Blackmon. The 6-foot-1, 207-pound wideout has already hauled in eight touchdowns on the year, leading all FBS receivers while helping the Cowboys to an early 3-0 mark. The rest of the Oklahoma State offense has been equally impressive, racking up an astounding 57.0 points per game. If the Cowboys can get by Texas A&M, Louisiana-Lafayette and Texas Tech over the next three weeks, they could be 6-0 heading into a home showdown with Nebraska.

Kansas State running back Daniel Thomas is generating early-season Heisman buzz after racing for 628 yards in the team's first four games, second in the FBS behind only Michigan's Denard Robinson. The Wildcats will need Thomas to be especially explosive this Saturday when they host Nebraska, the team's biggest test so far. Don't count out Bill Snyder's squad just yet, though. KSU is historically a much better team in Manhattan, winning over 72 percent of home games (compared to 32 percent of away games) from 2000-09. That home-field advantage has been even more pronounced of late: The 'Cats are 9-1 at Bill Snyder Family Stadium dating back to the beginning of last season.

The rest of Boise State's season might not be such a cake-walk after all. Following a 52-31 pasting of Cal on Sept. 17, Nevada steamrolled BYU with a dominating 27-13 performance last Saturday. If the Wolf Pack can keep afloat at Hawaii and Fresno State, they could host Boise on Nov. 26 for a shot at the WAC title. Spearheading Nevada's success is the two-headed rushing tandem of quarterback Colin Kaepernick and running back Vai Taua, both of whom have totaled over 450 yards on the ground through the first four weeks.

After waxing Miami (Ohio) 51-13 last Saturday, Missouri heads into a bye sporting a noteworthy 4-0 record. The Tigers face very winnable games in their next two contests (versus Colorado, at Texas A&M), which could make Missouri a surprising 6-0 heading into late October. That's when Blaine Gabbert and Co. will collide with Big 12 powerhouses Oklahoma and Nebraska. To pull those out, Missouri will need big showings from a defense that currently ranks sixth in the FBS with 13 turnovers.

Who currently leads the FBS in quarterback rating? Northwestern's Dan Persa, of course. Through four games, the junior signal-caller has posted a 186.3 rating while completing over 80 percent of his passes. If he keeps up his stellar play, Northwestern could crack the Top 25. The 'Cats don't face their first ranked opponent until Michigan State comes to town on Oct. 23, and they avoid playing Ohio State and Michigan during their relatively easy Big Ten slate.

Defense wins championships. That's what Texas A&M is banking on. The Aggies have held opponents to a meager 255 yards per game during their three opening victories. The competition -- Stephen F. Austin, Louisiana Tech and Florida International -- has been weak, though. The Aggies will need preseason All-Big 12 quarterback Jerrod Johnson to step up during impending matchups with Oklahoma State and Arkansas.

The Hoosiers are 3-0 to start a season for the first time since, well, last year. Indiana rolled to three straight wins in 2009 before dropping seven of its last eight to finish last in the Big Ten. The Hoosiers will try to avoid a similar fate this season, beginning with a brutal two-game stretch against Michigan and Ohio State starting this Saturday. Look for quarterback Ben Chappell, who's recorded a 9:0 touchdown-to-interception ratio thus far, to make the contests closer than anticipated.

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