Fox squeaks to sweeps victory in key demo

An unexpectedly vibrant sixth-season showing of “American Idol” helped power the Fox Television network to a surprising finish in the February prime-time sweeps that ended Wednesday -- first place in the highly coveted adults aged 18-to-49 demographic.

On the strength of America’s most popular television program, Fox squeaked into the top spot with a 5.2 rating/13 share in the “demo,” compared with a 5.0 rating/13 share for runner-up CBS, according to figures from Nielsen Media Research. The close finish was something of an upset given CBS’ enormous ratings windfall from its Super Bowl broadcast earlier in the month.

ABC (3.9/10) and NBC (2.9/8) were a distant third and fourth. Sweeps periods help local stations determine what rates to charge for ad time.

“We have faith in ‘American Idol,’ ” said Fox executive vice president and scheduling chief Preston Beckman. “We’ve done everything we can to protect the show and make it a once-a-year-event. We feel privileged to have it on Fox.”

CBS, which tends to do better among older viewers, could still brag about finishing first in total audience. Its airing of the Super Bowl and the Grammy Awards along with its “CSI” crime franchise helped it draw an average of 15.8 million viewers during the month, easily brushing past Fox’s 12.9 million. Trailing were ABC (10.3 million), NBC (8.6 million) and The CW (3.4 million).

“We had a great sweep,” said Kelly Kahl, CBS programming chief. “The Super Bowl helped a lot of our series hit season highs.”

The sweeps once were the sole determinant of quarterly advertising rates in television. With the spread of Nielsen’s local people meters, which provide immediate ratings feedback in such major market cities as New York, Los Angeles and Chicago, sweeps are relevant mainly in medium and smaller markets.

Of the four sweeps each year, February often produces the most ambiguous snapshot of each network’s true strength because it tends to be punctuated by events like the Super Bowl, the Grammys and the Oscars. And every four years, as they did in 2006, the Winter Olympics further muddy the ratings picture.

Still, every network can find something to crow about in any sweeps. ABC proclaimed victory in the 18-to-49 demo on Thursday nights thanks to the mega-hit “Grey’s Anatomy.” This marked the first time in 15 years that ABC won all the Thursday nights during a February sweeps. But the network has run into trouble elsewhere, and ratings for the Oscars were unspectacular, registering just a slight uptick from last year’s low numbers.

For NBC, the sweeps were disappointing despite being buoyed by hits “Heroes” and “Deal or No Deal.” Because it aired the Winter Olympics last year, the network was down nearly 40% in all major categories. The loss of Sunday football games because of the close of the NFL season hasn’t helped.

“We’re in the game. We have some encouraging signs things are coming together,” said Mitch Metcalf, NBC’s programming chief. “On the other hand, it’s not going to be a sweep we will long remember.”

martin.miller@latimes.com

scott.collins@latimes.com