* Mariah Carey, Nicki Minaj, Keith Urban debut as judges
* "American Idol" lost 'most-watched' crown last year
* Put focus back on contestants, critic says
LOS ANGELES, Jan 16 (Reuters) - "American Idol" returns on Wednesday with the tantalizing promise of fame, fortune and feuds - and that's just among the celebrity panel hired to find the next pop music sensation.
Singer Mariah Carey, rapper Nicki Minaj and country artist Keith Urban make their debut as judges when the TV talent contest begins its 12th season on Fox.
"All three judges are eminently qualified. It's a good spectrum in terms of embracing hip-hop, country and pop," HitFix.com music blogger Melinda Newman said.
"What everyone is going to be looking at, sadly, is how Mariah and Nicki Minaj get along, instead of focusing on the contestants," she said.
Carey, with more than 200 million album sales, the outspoken Minaj, one of the most exciting voices in rap, and Urban are expected to revive interest in the contest. Last year average audiences dipped below 20 million, and "Idol" lost its eight-year crown as the most watched show on U.S. television to NBC's "Sunday Night Football."
The three newcomers replace departing judges Jennifer Lopez and Aerosmith frontman Steven Tyler who quit last year after two seasons.
The new panel, rounded out by old hand record producer Randy Jackson, didn't come cheap. Carey is reported to be earning approximately $18 million for the season, Minaj about $12 million and Urban $8 million.
But industry watchers say "Idol" needs more than big names to bring in audiences at a time of cutthroat competition from talent contests like "The Voice," "The X Factor," and "America's Got Talent."
"While shaking up the show can initially provide curiosity tune in, at the end of the day, the panel needs to click with each other and with fans," Entertainment Weekly's James Hibberd said.
"'Idol' used to have the playground all to itself. After four months of 'The Voice' and ' X Factor' last fall, are audiences still going to be excited by 'Idol'?" Hibberd asked.
The new season of "Idol" was making headlines in September, when video of Carey and Minaj arguing during early auditions was leaked online.
Minaj also was reported to have threatened to shoot Carey, who said in a TV interview last week that she had hired extra security while filming the show.
FOCUS ON CONTESTANTS
In a tense media appearance last week, the two divas claimed they had put their feud behind them, attributing the fight to passionate differences of opinion about the contestants auditioning for a chance to make it through to later rounds.
Newman said it would be a shame if the fight overshadows the show's original mission of finding new talent, an achievement that could prove the biggest boost to "Idol" ratings.
"All these shows have become more about the contestants than the judges. It would be nice if 'American Idol,' as the one that started it all, got the focus back on the contestants.
"Ten years ago, people were really excited when they were voting for ('Idol' winners) Kelly Clarkson or Carrie Underwood. There needs to be a powerhouse group of contestants who really capture people's interest, and who you want to root for," Newman said.
The new judges say that's what they want too.
"When I watch these shows and someone says yes to a person who clearly doesn't deserve it, it bothers me," Minaj told TV reporters last week. "And I want to jump through the TV because I feel like, for the people who are talented, it kind of minimizes how talented they really are. So when I came on, I didn't really have a problem with saying no, because I kind of felt like we're looking for the best of the best."
Aspiring rappers - never a group that has been embraced by "Idol" producers or fans - will get short shrift.
"I definitely don't think a rapper should be in this competition ... When I got involved in the competition, I specifically said, I hope they didn't try to do that because I was on the show, because I think America loves that it's an honest singing competition," Minaj said.
"American Idol" kicks off on Wednesday on Fox with a two-hour premiere, followed by a one-hour show on Thursday. Fox is a unit of News Corp.