Fast National ratings for Thursday, February 7, 2013.
 
After already crushing "American Idol" in their first head-to-head battle of the season last week, CBS' "The Big Bang Theory" posted big gains on Thursday and helped the network expand its overall margin of victory.
 
Among other notables, the fourth season premiere of NBC's "Community" was up over where the comedy left off last May, while ABC's "Scandal" hovered around yet another series high for a pivotal episode. And as for that hypothetical Super Bowl bounce, CBS' "Elementary" was up, but only by a small margin.
 
And, finally, after an already dismal premiere, NBC's "Do No Harm" found a way to take a big drop in its second airing.
 
On to the numbers...
 
Among adults 18-49, CBS averaged a 3.5 rating, beating FOX's 3.1 rating for Thursday night in the key demographic. ABC was third in the key demo with a 2.4 rating, far ahead of the 1.4 key demo rating for NBC. The CW's 0.8 key demo rating trailed for the night.
 
Overall, CBS averaged an estimated 14.23 million viewers and an 8.8 rating/14 share, leaving FOX a distant second with a 5.7/9 and 9.61 million viewers. ABC was third with a 4.9/8 and 7.2 million viewers, more than doubling the 2.0/3 and 3.21 million viewers for NBC. The CW averaged a 1.3/2 and 2.01 million viewers for the night.
 
[Univision averaged 4.04 million viewers and a 1.6 rating among adults 18-49 for Thursday primetime.]

8 p.m. - "The Big Bang Theory" (18.85 million viewers and a 6.1 key demo rating) and "Two and a Half Men" 14.145 million viewers and a 4.1 key demo rating) dominated the 8 p.m. hour for CBS, with "Men" holding off "Idol" overall in the second half-hour. "American Idol" slipped to 13.15 million viewers and a 4.1 rating among adults 18-49 to put FOX in second for the hour. There was a huge drop to the 4.78 million viewers for ABC's "Shark Tank" repeat, which finished fourth in the key demo with a 1.3 rating. NBC was fourth overall and third in the key demo with encouraging weeks for "Community" (3.98 million and a 1.8 key demo) and "Parks and Recreation" (3.83 million and a 2.0 key demo rating). The CW's "The Vampire Diaries" had a down week with 2.5 million viewers and a 1.1 key demo rating.
 
9 p.m. - "Person of Interest" lost a few viewers to 15.16 million and stayed steady with a 3.2 rating among adults 18-49 to win the 9 p.m. hour for CBS. ABC's "Grey's Anatomy" was up with 8.82 million viewers and a 3.1 key demo rating. FOX's "Glee" was up with 6.06 million viewers and a 2.2 key demo rating. NBC was fourth with "The Office" (4.25 million viewers and a 4.25 million viewers) and a disconcerting drop to "1600 Penn" (2.81 million viewers and a 1.1 key demo rating). The CW's "Beauty and the Beast" was down with 1.52 million viewers and a 0.6 key demo rating.
 
10 p.m. - "Elementary" won the 10 p.m. hour with 11.02 million viewers and finished second with a 2.3 rating among adults 18-49. ABC's "Scandal" averaged just under 8 million viewers and an hour-winning 2.8 key demo rating, which either will or won't be a series high once final figures come in. NBC's "Do No Harm" dropped to 2.18 million viewers and a 0.7 key demo rating in its second airing.
 
All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.