A record-setting AFC Championship game on Sunday vaulted CBS to an easy primetime ratings victory last week, logging the best scores for any network this season.

The Eye also padded its lead in the season race, where it tops Fox in the adults 18-49 demo by about a 10% margin at the halfway point. While Fox can count on massive numbers for the Super Bowl on Feb. 6, it also figures to win virtually every week through season’s end in May thanks to “American Idol.”

The Eye won most of the weeks in the fall and possesses the season’s top new shows, but that may not be enough to end Fox’s six-year winning streak in adults 18-49. CBS has received little help from its limited-run midseason competition series “Live to Dance,” and none of its upcoming midseason skeins looks to be a breakout.

Still, if nothing else, CBS should make Fox sweat a bit — especially if “Idol” becomes even more mortal the rest of the way.

Fox, meanwhile, bolstered its fortunes by plugging the black hole that is Friday. Last week, it actually won the night among young adults with its new lineup anchored by former Thursday drama “Fringe.”

“Idol” may have come back with a lower opening-night number than last year (Daily Variety, Jan. 21), but it still towers over every other entertainment series of this season.

Overall for the week of Jan. 17-23, according to Nielsen, CBS cruised to victory with a 4.9 rating/14 share in adults 18-49, followed by Fox (3.6/10), ABC and NBC (both 1.7/5), Univision (1.3/4) and top cabler MTV (1.0/3).

The Eye also had it in adults 25-54 (6.0/15) and total viewers (17.2 million) — two categories it figures to keep in its corner for the season. A victory for the season in total viewers would be the net’s eighth in the past nine years.

Looking at the week, football’s AFC Championship on Sunday between the Pittsburgh Steelers and New York Jets averaged a monster 19.7 rating/46 share in adults 18-49 and 54.85 million viewers overall — a record audience for the game. It also lifted the special episode of “Hawaii Five-0” airing after it to best-yet scores (5.6/15, 19.33m) as the net was looking to give the rookie drama additional sampling.

Among regular series, “Two and a Half Men” (4.6/11, 15.56m), “The Big Bang Theory” (4.2/12, 13.63m) and “NCIS” (4.1/12, 21.09m) all ranked in the top 10, with “Big Bang” retaining more than 90% of its prior season average despite facing Fox’s “American Idol.”

Also, “Blue Bloods” made a decent debut Wednesday (2.0/6 in 18-49, 12.30m), winning its hour in 25-54 (3.1/8), and “Medium” went out with season highs Friday (1.6/5, 7.87m).

At Fox, “Idol” kicked off its 10th season in dominant fashion Wednesday (9.7/26 in 18-49, 26.23m) and its regular-night debut on Thursday (7.8/21, 22.90m). It was down in 18-49 vs. the opening nights of last year (Tuesday and Wednesday) by 18% and 23%, respectively, but still locked up the top two ratings for any entertainment telecasts this season.

A less-heralded highlight for Fox came Friday, where “Kitchen Nightmares” (1.9/6 in 18-49, 4.27m) and “Fringe” (1.9/6, 4.87m) tied for the evening’s top show in 18-49 and gave the net its strongest rating on the night with regular programming since September 2008. “Fringe,” which matched its prior Thursday average, is among the season’s biggest percentage gainers in full-week DVR playback.

NBC improved Monday, when “Chuck” edged up to a season high, though it still ran fourth for its hour (2.1/5, 5.97m), and “Harry’s Law” had a solid debut at 10 o’clock (2.2/6, 11.07m). “Harry’s” also held up well in its second outing on Monday of the current week (2.1/6, 10.43m).

Not as promising is another Monday newcomer, “The Cape” (1.8/4, 6.22m), which dipped further this week (1.6/4, 5.85m).

The Peacock saw its new six-comedy Thursday lineup get off to a good start, racking up the net’s best 18-49 score on the night (2.8/7) in 10 months. “The Office” (4.5/12, 8.26m) was Thursday’s top scripted series, leading into series highs for the season preem of “Parks and Recreation” (3.2/8, 6.14m); and “30 Rock” (2.7/7, 5.34m) and “Outsourced” (1.8/5, 3.95m) moved into the 10 o’clock hour and improved the Peacock’s standing.ABC’s best news came Wednesday, where “The Middle” (2.6/8 in 18-49, 8.32m) and “Modern Family” (4.6/12, 10.94m) held up well against “Idol.” “Family” was the week’s No. 1 regular scripted program in 18-49 and figures to gain substantially in same-week DVR playback; its first original of 2011 (on Jan. 3) jumped up a record 1.7 ratings points from “same night” (4.8) to full-week DVR playback (6.5).

In cable, MTV’s “Jersey Shore” set series records for a third straight week, dominating its Thursday hour in 18-49 (4.7/13, 8.87m). And a special Monday hour (3.9/9, 7.70m) helped provide a strong lead-in for “Skins” (1.5/4, 3.26m), which led all of television in the 10 o’clock hour among adults 18-34 (2.4/8).

The network also continues to do very well with “Teen Mom” (2.1/6, 3.66m).

USA launched Thursday drama “Fairly Legal” to decent numbers (1.1/3, 3.88m), airing behind the winter preem of “Royal Pains” (1.1/3, 4.43m); neither did as well in the demo as the net’s winter return of Tuesday drama “White Collar” (1.3/4, 3.81m).

At Starz, Friday’s debut of “Spartacus: Gods of the Arena” averaged 1.10 million viewers with its premiere and another 750,000 viewers for its same-night repeat; the 1.85 million viewers reps a big gain over the 1.09 million for the opening night of “Spartacus: Blood and Sand” a year ago.

And at E! on Sunday, “Kourteney and Kim Take New York” (1.8/5, 3.43m) opened its season above last year, hitting a series high in women 18-34 (3.5/10), standing as Sunday’s top-rated regular primetime series (broadcast or cable) in the demo.