Cobie Smulders

The Mother of all Robin-centric How I Met Your Mother episodes brought the series its largest audience in nearly three years, while 2 Broke Girls anted up its biggest viewership since its September premiere in the first hour of prime time, according to Nielsen overnight data. The second half of CBS' two-hour Monday comedy block ran up the numbers too, as Two and a Half Men attracted the night's biggest audience, as well as the highest rating in the industry-coveted 18-to-49 demo.

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Meantime, Fox's broadcast of the American Country Awards improved on its inaugural outing last year by 23 percent in viewership and 33 percent in the demo. In other news, it looks like it's a good thing Chris Harrison has his Bachelor and Bachelorette franchises to fall back on, as a stingy 3.57 million tuned in to the second episode of You Deserve It.

And with such a weak lead-in, ABC's Castle got handcuffed in second place to Hawaii Five-0, which won the 10 o'clock timeslot.

8 p.m.
CBS: How I Met Your Mother 11.71 million viewers (4.5 demo rating); 2 Broke Girls 12.78 million (4.6)
ABC: A Charlie Brown Christmas 9.06 million (2.8); Prep & Landing 2: Naughty vs. Nice 6.99 million (2.2)
Fox: American Country Awards 7.42 million (2.0) {8-10 p.m.}
NBC: The Sing-Off Christmas Special 4.13 million (1.1) {8-10 p.m.}
CW: Gossip Girl 1.28 million (0.6)

9 p.m.
CBS: Two and a Half Men 15.04 million viewers (5.0 demo rating); Mike & Molly 12.74 million (4.2)
ABC: You Deserve It 3.57 million (1.0)
CW: Hart of Dixie 1.79 million (0.8)

10 p.m.
CBS: Hawaii Five-0 10.76 million viewers (3.0 demo rating)
ABC: Castle 8.05 million (2.0)
NBC: Rock Center with Brian Williams 3.42 million (0.9)