Who will replace Steven Tyler, Jennifer Lopez on American Idol?

In this May 25, 2012 file photo, singer Mariah Carey poses before a press conference, during the Mawazine Festival in Rabat, Morocco. Mariah Carey, Usher and Celine Dion are among the heady names being tossed around as "American Idol" replacement judges after the exits of judges Steven Tyler and Jennifer Lopez. (AP Photo/Abdeljalil Bounhar, File)

Associated Press

LOS ANGELES Mariah Carey, Celine Dion and Mary J. Blige are among the heady names being tossed around as potential judges for "American Idol" after Steven Tyler and Jennifer Lopez skipped out on next season.

Star power, after all, is what judges add to TV talent shows that otherwise feature unknowns whose performances can range from surprisingly good to stunningly awful.

But Fox's "American Idol," trying to right itself after shedding viewers in its 11th season, may also need to play a numbers game as in the age of the judges brought in to revitalize a show whose audience is getting smaller and older, neither a plus for advertisers.

"They need judges who will resonate with young people," said media analyst Brad Adgate.

Carey, Dion and Blige, undeniably winning stars, all are in their early 40s.

The median age for the "American Idol" audience rose above 50 last season, the first time ever, and Adgate suggests it take a page from "The X Factor" playbook, as devised by its creator and producer, Simon Cowell.

"Cowell beat them to the punch" by hiring Britney Spears and Demi Lovato after "X Factor," t! he Fox v ersion of Cowell's British hit, stumbled in its debut last season. Spears, 30, and Lovato, 19, replaced Paula Abdul, 50, and Nicole Scherzinger, 34.

(Worth noting: The male judges, Cowell, 52, and producer Antonio "L.A." Reid, 56, are staying put for season two.)

Lopez announced her departure on Friday, a day after Tyler (an unlikely senior statesman at 64) said he was leaving "American Idol" to concentrate on his role as Aerosmith's frontman. Both appeared for two seasons.

Fox may be scouting for an entirely new panel, with some reports suggesting that original "Idol" judge Randy Jackson, 56, could shift to another role while Carey, whom he manages, becomes a judge.

The makeover comes at a critical time. In May, "American Idol" posted its lowest-rated finale ever after a season that marked its poorest showing yet among young adult viewers age 18 to 49.