Fox television heads into the year’s biggest advertisement sales period later this month with questions about the future of its ratings champ ‘American Idol’ - shown here in Dubai on MBC 4.

But according to experts, a better economy, among several other factors, should buoy the show’s ad revenue.

Viewership has slipped on the singing contest, and its hold on the No. 1 position in US TV is being challenged.

Fan buzz among America’s music-loving youth seems to have shifted to musical ‘Glee’, and at the end of this season, top Idol star, judge Simon Cowell, will leave the programme.

Fox executives said there will be no announcement on Cowell’s successor when the network presents its 2010 to 2011 programmes to advertisers at their annual ‘upfront’ presentation on May 17, or before the American Idol finale on May 26.

But like a struggling contestant getting a ‘judge’s save’ on Idol which gives that person another chance to compete viewer-based advertising is being propped up by signs of recovery in the ad market, as well as by Idol’s continued dominance over most of its rival TV shows, analysts said.

“I don’t think they will be able to get sky-high prices. But advertisers still need mass audiences, and although the show is getting fewer people watching, they are still getting the biggest crowd you can get,” said Brian Steinberg, TV editor of Advertising Age.

Yet, it is hard to deny Idol is seeing its blockbuster status challenged. In February, it was twice beaten by NBC’s Winter Olympics, and recently ABC’s ‘Dancing With the Stars’ has claimed  the title of ‘most-watched TV series’ by all viewers on a couple of nights.

Steinberg said anecdotal evidence suggests Fox is getting about $1 million for a 30-second ad in this year’s Idol finale, down from $1.3 million in 2007.

Fox does not disclose such ad sales figures.

But those ads were sold when the economic outlook was more bleak and advertisers were slashing budgets.

Ahead of the upfronts, the sentiment for 2010 to 2011 seems to be shifting. The TV networks use upfronts to present future season’s shows, and then they start negotiating rates with ad buyers for the next year.

Barclays Capital media analyst Anthony DiClemente said in a recent research note that he expected upfront dollar volume for the leading four TV networks to increase 20 per cent from 2009 to $8.26 billion, partly due to improved corporate confidence.

Yet, even as the ad market appears to be rebounding, Idol faces the departure of popular British judge Cowell, who is
quitting to launch his own TV show on Fox in late 2011.

“Simon is irreplaceable. He is the star of the show. So you don’t try to fill his shoes, you go in another direction,” said Mike Darnell, president of alternative programming at Fox.

But he declined to say what that direction will be.