Though the NFL season kickoff may have dipped compared with last year, NBC was still by far the dominant network last night, with its football game and Republican National Convention coverage outpacing the other networks.

NBC averaged a 4.7 adults 18-49 rating and 13 share for the evening, according to Nielsen overnights, nearly double No. 2 Fox’s 2.4/7.

As a reminder, fast nationals measure timeslot and not actual program data. The NFL game kicked off an hour before primetime started, at 7 p.m., and the RNC coverage didn’t end until after 11 p.m. Thus numbers for NBC, and for ABC and CBS’s political coverage, are approximate and could change a lot when final results are released this afternoon.

According to metered markets, the NFL game averaged a 10.7 household rating from 7:15 to 10 p.m. From 8 to 10, the New York Giants’ win over the Washington Redskins averaged a 5.4 adults 18-49 rating, though that was down quite a bit from last year’s 6.8 for the Indianapolis Colts’ win over the New Orleans Saints during primetime.

The game may have been impacted by RNC coverage, which has been drawing big ratings on cable, as well as Fox News Channel’s much-hyped Bill O’Reilly interview of Democratic presidential contender Barack Obama, which aired last night.

For the night, CBS placed third at 1.8/5, Univision fourth at 1.6/5, ABC fifth at 1.2/3 and CW sixth at 1.0/3.
 
At 8 p.m. NBC led with a 5.0 for its coverage of the NFL game between the Giants and Redskins, while CBS and Fox tied for second at 2.2, CBS for “Big Brother” and Fox for the first half of a “Kitchen Nightmares” clip show. Univision was fourth with a 1.8 for “Al Diablo con los Guapos,” ABC fifth with a 1.0 for a repeat of “Ugly Betty” and CW sixth with a 0.9 for a repeat of “90210.”
 
NBC was first again at 9 p.m. with a 5.8 for more football, followed by Fox with a 2.6 for the second half of “Nightmares.” CBS was third with a 1.9 for a repeat of “CSI,” Univision fourth with a 1.8 for “Fuego en la Sangre,” ABC fifth with a 1.2 for a “Grey’s Anatomy” rerun and CW sixth with a 1.0 for the second hour of the “90210” repeat.
 
At 10 p.m. NBC finished first with a 3.2 for its coverage of the Republican National Convention, with CBS second with a 1.4 for its RNC coverage. Univision and ABC tied for third at 1.3, both for the RNC.
 
NBC also led the night among households with a 7.5 average overnight rating and a 12 share. CBS was second at 4.2/7, Fox third at 3.3/5, ABC fourth at 3.2/5, Univision fifth at 2.1/3 and CW sixth at 1.5/2.