Late-season NFL action carried NBC to a second straight primetime ratings victory in key demos during the final frame of 2007, a week littered with repeats.

The Peacock’s “Sunday Night Football” matchup between Tennessee and Indianapolis — which decided the final entrant into pro football’s playoff field — was the highest-rated single-network program of the week. Technically, however, it wasn’t the top draw.

That honor goes to the unprecedented three-network simulcast — on CBS, NBC and NFL Network — of Saturday’s historic victory by the New England Patriots over the New York Giants. The Pats won the game 38-35 to cap the first undefeated regular season in the league in 35 years.

On average, nearly 34 million viewers watched the game on one of the three networks, while nearly 1 million more watched on additional outlets in the local markets of New York, Boston and Manchester, N.H.

CBS, which airs more Patriots games than any other network, unsurprisingly held the edge with 15.68 million viewers, while NBC drew 13.23 million. The young NFL Network, available in less than half the country, added 4.49 million to the total.

Overall for the Dec. 24-30 frame, Nielsen estimates that NBC prevailed in adults 18-49 with a 2.7 rating/8 share, followed by CBS (2.3/7) and Fox (2.2/7). A lackluster ABC (1.6/5) barely edged out ESPN (1.5/4) and Univision (1.4/4).

The Peacock also led in adults 25-54 (3.2/9) and persons 12-34 (1.8/7, tied with Fox), while CBS edged past NBC to win among total viewers (8.6 million to 8.2 million).

Leading the way for NBC was “Sunday Night Football” (5.9/15 in 18-49, 15.80m), which crushed its mostly repeat competish and helped the net win the night in demos for the 11th time this season.

Also during the week for NBC, the Peacock’s 23rd airing of “It’s a Wonderful Life” was a popular choice on Christmas Eve (1.5/5 in 18-49, 4.49m), while a new two-hour “Deal or No Deal” was the top program on Christmas night (2.6/8, 9.78m).

Net also got off to a good start in the new year, with a couples edition of “The Biggest Loser” on Tuesday of the current week producing the best premiere ratings to date for the franchise (prelim 4.3/10 in 18-49, 10.4 million viewers overall).

CBS was paced by Saturday’s NFL game, which gave the net its best numbers on the night in more than two years. Net is sure to eclipse that mark next week, however, as the Patriots open the playoffs with a Saturday evening contest on the Eye.

Top entertainment programs of the week for CBS was Sunday’s “Amazing Race” (2.9/7, 9.69m) as the globetrotting reality series heads for this season’s finish line in a couple of weeks.

Fox didn’t have much to boast about, although it did pretty well Wednesday through Friday with theatricals “Christmas With the Kranks” (2.4/7 in 18-49, 7.24m), “Ice Age” (2.1/6, 6.17m) and “Bruce Almighty” (1.9/6, 5.27m).

And ABC would like to forget about the week, in which no telecast did better than a 2.0 rating in 18-49. Ditto CW, whose “Crowned” is getting crushed on Wednesday (0.7/2, 1.58m).

ESPN claimed the week’s top two primetime cable telecasts with the Christmas Eve “Monday Night Football” game between San Diego and Denver (3.3/12 in 18-49, 8.76m) and Thursday’s Holiday Bowl college game between Texas and Arizona State (1.8/6, 5.70m).

A standout on the entertainment side was TBS’ “Funniest Commercials of the Year: 2007” on Wednesday (2.1/6 in 18-49, 5.09m). It was up vs. the previous year’s spec and stood as the top-rated program on television for the night among adults 18-34 (1.9/6).