NBC’s high-profile attempt to cash in on the singing craze was a success on Tuesday. Airing against stiff competition (a two-hour Dancing With the Stars! A special 90-minute episode ofGlee!), The Voice was the No. 1 show of the night in the all-important 18-49 demographic.

The two-hour show pulled a 5.1 rating/13 share in the demo and 11.8 million viewers, according to early estimates. NBC says that it was the top-rated series premiere on a major network since Undercover Boss debuted following the Super Bowl on Feb. 7, 2010. Each 18-49 ratings point equals 1.3 million.

Head to head, The Voice beat Glee (4.6 versus 3.4 from 9-9:30) and Dancing With the Stars(4.9 versus 3.5 from 9-10). It improved the time period versus NBC’s season average in the demo by 89 percent (5.1 versus 2.7) and in viewers by 60 percent (11.7 million versus 7.3 million). Excluding sports, the 5.1 rating achieved by The Voice was NBC’s highest in the time period since May 12, 2009.

Other notable highs/lows: Glee was down 11 percent from last week; it was also a season low for the dramedy. The last time it posted such a low rating was on Nov. 25, 2009 (a measly 2.5). The DWTS results show, however, was up 17 percent in the demo.

CBS shrewdly bowed out of the heavy competition and ran repeats of NCIS, NCIS: LA andThe Mentalist. Other shows suffered from the intense interest in The Voice: an original ofRaising Hope on Fox earned a 1.9/5 — down 10 percent from last week — while Body of Proof posted its lowest 18-49 rating to date on ABC (2.3/6).

ABC won the night in total viewers (14.3 million), followed by NBC (10.3 million). The DWTSresults show was the most-watched show of the night with 17.9 million eyeballs.

One final (and fun!) ratings tidbit: The last time an NBC show opened big was on Jan. 6, 2008. The show? American Gladiators. It earned a whopping 5.9/14 in the demo. Too bad it didn’t last long. Maybe Christina Aguilera will have a better chance.

Source: EW