It’s been a wild college football season, with five teams already holding the No. 1 spot in the Associated Press and three undefeated squads currently battling for the top two spots in the Bowl Championship Series standings.

Perhaps it’s no surprise, then, that college football viewership is up.

Through 137 telecasts across six networks, games are averaging 2.7 million total viewers, up 8 percent over last year at this time, when 148 games had averaged 2.5 million viewers.

That’s according to Nielsen estimates for ABC, CBS, NBC, ESPN, ESPN2 and Versus, the six major college football carriers.

Viewership is also up 4 percent in the key demo of men 18-49, from an average 817,000 last year to 846,000 this year. It’s flat among men 18-34 at 397,000, compared to 398,000 last year.

The up ticks come as no surprise to anyone who’s followed the sport this season. It’s been one of the more exciting and suspenseful in recent history.

Four undefeated No. 1 teams have been knocked off: Georgia, USC, Oklahoma and, most recently, Texas.

That’s helped push up ratings for marquee matchups including last Saturday’s primetime Texas-Texas Tech contest, in which the Red Raiders scored a final-seconds victory over the previously undefeated Longhorns.

That drew ABC’s biggest “Saturday Night Football” audience in almost two years, averaging 11.2 million total viewers and a 4.0 rating among adults 18-49.

The victory sent undefeated Texas Tech soaring in the polls and pushed Alabama into the top spot, the fifth team to hold it this year.

The Red Raiders, Crimson Tide and Penn State are all currently undefeated and battling for the top two spots in the BCS in order to play for the national championship.

The Nittany Lions have the easiest schedule ahead, including two unranked teams, plus they will not have to play in a season-ending conference championship. The Big Ten does not hold one, unlike the Big 12 and the SEC.

Meanwhile, Alabama faces LSU this weekend and the Red Raiders play Oklahoma State, both ranked teams who could stir up the rankings even further.