Britney Spears and Simon Cowell attend "The X Factor" season two premiere at Grauman's Chinese Theatre on Tuesday, Sept. 11, 2012, in Los Angeles.Jordan Strauss
The much-hyped return of Fox singing contest The X Factor stumbled with Americans, despite the arrival of new judge Britney Spears, drawing a smaller audience than last year and getting drowned out by rivals The Voice and America's Got Talent on NBC.
Preliminary Nielsen ratings on Thursday showed that an average 8.5 million Americans – about 3.5 million down from the 2011 opener – watched Spears and singer Demi Lovato make their debuts in the two-hour season premiere of X Factor on Wednesday.
But on NBC, about 11 million tuned into the finale of America's Got Talent and 10.7 million watched a third episode this week of The Voice.
NBC emerged as the most-watched U.S. network of Wednesday night, but Fox was the winner in the 18-49 age group most prized by advertisers.
The Voice, the brightest light in struggling NBC's programming for several years, was moved this year to two seasons a year in a closely watched decision that put the singing contest compete for viewers with British entrepreneur Simon Cowell's revamped The X Factor on Fox.
Spears, the biggest pop phenomenon of the 2000s with hits like Toxic and Womanizer, was recruited by Cowell earlier this year after he fired two X Factor judges after a disappointing first season. Spears, 30, is reportedly being paid around $15-million (U.S.) a year.
But Spears and former Disney Channel star Lovato were a hit on social media. Social TV analytics firm Bluefin Labs said that X Factor triggered about 1.4 million comments on Twitter, Facebook and other social-media platforms on Wednesday, making it the most social season premiere of all time.
Fox is a unit of News Corp and NBC is majority-owned by Comcast.