The Sunday finale of “Survivor: Cook Islands” helped cap a strong ratings week for CBS, which has caught ABC for the season lead among young adults.

Eye net ran four hours of the reality adventure series, which can still pack a ratings punch 6½ years after its spring 2000 premiere. The “CSI” franchise and other crime skeins like “NCIS,” “Criminal Minds” and “Numbers” also pitched in for CBS.

Consistency has been key for the net: Last week repped its first outright victory of the season in the key 18-49 demo, but it was competitive enough during ABC’s winning frames earlier this season that it was in position to gain ground for the season race when the Alphabet’s hot series went into repeats or were off the sked altogether after the November sweep.

And the same consistency holds true on a night-by-night basis, as CBS placed first or second in adults 18-49 and other key measures every night of last week.

For the season, ABC and CBS are both at a 3.9 rating, according to Nielsen, with an improved NBC at 3.7 and Fox well behind the pack at 3.0.

ABC and CBS are expected to battle for the season lead right down to the wire in May, with Fox also having a good shot at challenging if “American Idol” comes back near where it was a year ago. CBS also is looking good in adults 25-54 and total viewers, holding a comfortable advantage in both categories.

Looking at Nielsen nationals for the week of Dec. 11-17, CBS won easily in the adults 18-49 demo with a 3.7 rating/10 share, followed by NBC (3.2/9), Fox (2.9/8) and ABC (2.5/7).

Univision, with its hot weeknight skein “La Fea Mas Bella” hitting series-best scores, placed a solid fifth for the frame (1.7/5), well ahead of the CW (1.0/3), which aired almost all repeats. Week also included good performances for the finales of cable skeins “Dexter” on Showtime and “Nip/Tuck” on FX.

Fox’s original episode of “House” was the week’s No. 1 telecast in key demos including adults 18-49 (6.5/17) and 25-54 (7.2/17), while CBS’ “NCIS” led in total viewers (17.39 million). It was the first time the fourth-year military crime skein has topped the weekly ratings in total viewers.

CBS claimed seven of the week’s top 10 programs in adults 18-49, paced by the finale of “Survivor: Cook Islands” on Sunday (5.7/14, 16.42m), which came in 26% below the “Survivor: Guatemala” finale of last December (7.7 rating) and off 8% from last May’s Panama finale (6.2). Hourlong “Survivor: Cook Islands” reunion show performed well to finish off Sunday for the Eye (5.1/13, 13.53m).

CBS remained strong on Wednesday with “CSI: NY” (4.9/14, 15.83) and “Criminal Minds” (4.7/12, 16.06m), and won Friday with its all-original lineup of “Ghost Whisperer” (2.9/10, 9.66m), “Close to Home” (2.5/8, 9.65m) and “Numbers” (3.1/10, 11.23m).

It also was a good week for the net’s middle-hour Monday comedy block of “Two and a Half Men” (5.1/13, 15.69m) and “Old Christine” (4.1/10, 11.96m), both of which hit two-month highs.

NBC, which showed gains compared to the same frame a year ago for the eighth straight week, was led by the “Sunday Night Football” game between San Diego and Kansas City (5.8/14 in 18-49, 15.26m), the No. 2 show in 18-49 and No. 1 in most male demos.

Net also did well with Monday’s “Deal or No Deal” (4.6/13, 16.70m), but the same night’s original movie “A Year Without Santa Claus” did not produce especially jolly ratings (2.5/6 in 18-49, 7.40m).

And Wednesday’s two-hour conclusion to “The Biggest Loser 3” was a ratings winner (4.8/13, 11.73m), although it was down vs. last year’s second-season finale.

At Fox, the few highlights aside from “House” came from Sunday animated laffers “The Simpsons” (4.4/11 in 18-49, 8.88m) and “Family Guy” (4.5/10, 8.91m). Earlier in the day, the net’s NFL game between the Philadelphia Eagles and New York Giants averaged a big 21.2 million viewers — making it the week’s most-watched program even though it was out of primetime.

Things were bleaker at ABC, which cracked the top 20 in 18-49 with only Sunday’s net preem of “The Santa Clause 2” (4.6/11 in 18-49, 13.67m) and Tuesday’s repeat of the animated classic “Dr. Seuss’ How the Grinch Stole Christmas” (3.9/11, 10.96m).

Disappointments included Wednesday’s combo of “Show Me the Money” (1.6/5 in 18-49, 6.32m) and “Day Break” (1.4/4, 3.94m), both of which have since been canceled.

On the cable side, even though ESPN’s Chicago-St. Louis “Monday Night Football” matchup (4.4/13 in 18-49, 11.15m) was the week’s No. 1 program, USA (led by Monday’s “WWE Smackdown”) topped the sports net for the lead in most key categories.

Week’s top scripted 18-49 programs on cable were FX’s fourth-season finale of “Nip/Tuck” on Tuesday (1.8/5 in 18-49, 3.38m) and Sunday’s repeat airing of “National Lampoon’s Christmas Vacation” (1.9/4, 4.25m).

“Nip” finished as cable’s No. 1 scripted skein in 18-49 (2.75 million in the demo), up slightly from its third season (2.7 million).

At Showtime, “Dexter,” which scored a Golden Globe nom for star Michael C. Hall, scored 1.1 million overall viewers Sunday night (including 692,000 adults 18-49).

Episode ranks as the pay cabler’s most-watched series seg since 2004, and the net’s most-watched telecast — original or acquired — of the year.

Audiences for “Dexter” built over the show’s 12-episode run, with the season ender up 44% from the premiere (603,000 viewers).

(Denise Martin contributed to this report.)