Standing beside a swimming pool overlooking the Los Angeles skyline, the British TV mogul Simon Fuller congratulated the latest American Idol at a private party on Wednesday night — but the real winner was undoubtedly Mr Fuller who, for seven years, has dominated America's TV ratings and made himself a dollar billionaire.

At the end of a celebrity-filled two-hour show, this year's winner was revealed to be David Cook, a soulful Missouri rocker who built up a fanbase by performing grunge versions of Lionel Richie's Hello and Michael Jackson's Billie Jean.

Mr Cook, 26, prevailed in spite of what many regarded as a superior finals night performance by his more wholesome rival David Archuleta, 17.

The numbers spoke for themselves: a record 97.5 million votes were cast by viewers of the singing contest — with Mr Cook getting approximately the same number of votes that President Bush received in the 2004 general election.

“We're still a goliath,” Mr Fuller told The Times, referring to the status of the show — a spin-off from Britain's Pop Idol — as the most-watched show in the US. “We're still bigger than anything else, and now David Cook is going to sell millions of records for us.”

With ratings declining and criticism of American Idol mounting — including accusations of vote rigging — many are asking how Mr Fuller and his British executives can continue to make such spectacular amounts of money out of an ageing franchise.

The genius of the show is that Mr Fuller makes money out of the talent-scouting process and cashes in again if the stars of the show sell millions of records — as has happened with Kelly Clarkson, Carrie Underwood, Chris Daughtry, Jennifer Hudson (who also won an Oscar) and others.

The show — which is broadcast on the Fox network, part of News Corporation, parent company of The Times — is thought to earn at least $500 million (£253 million) a year from advertising and sponsorship deals, with 30-second slots during the final selling for $780,0000 each.

The show also makes money from the text message and telephone voting, a post-season tour, CDs, merchandise and — as of this year — live, on-the-night performances sold via the Apple iTunes store.

The magazine Advertising Age valued the entire franchise recently at $2.5 billion.

Although the show has made a celebrity out of Simon Cowell, thanks largely to his willingness to put unflinching criticism ahead of the feelings of contestants, few Americans are aware that the production is an entirely British creation.

Apart from Mr Fuller and Mr Cowell, the co-executive producers are Ken Warwick and Nigel Lythgoe, also Britons. Even the director, Bruce Gower, is British.

But the expats have a difficult job ahead of them for next season. For most of the show's run this year ratings were off by about 10 per cent.

This was blamed on the aftermath of the writers' strike, which drove viewers away from television, and results from the Democratic Party's primary race, which came in on Tuesday nights at the same time that American Idol was on the air.

Critics complained of being bored with the format and Paula Abdul, one of the judges, made a gaffe when she gave her verdict on a contestant before he sang, revealing that her notes had been scripted in advance.

The show staged a recovery for the finals. On Tuesday, when the contestants gave their last performances, ratings were up 7 per cent on 2007, to 27 million.

The following night, when the results were revealed, the ratings were up 4.5 per cent, to 26.5 million, according to preliminary data. But executives were clearly rattled.

At the party on Wednesday Mr Fuller promised radical changes for next season, with rumours suggesting that a fourth judge would be hired to join Mr Cowell, Ms Abdul and Randy Jackson.

“There's going to be a big shake-up,” confirmed Mr Cowell, who spent most of Wednesday evening with the $12.5 million-a-year host of Idol, Ryan Seacrest. “You'll see.”

Gaining the votes

27m Voters in the 2005 British general election

6.4m Votes were cast during the 2004 final of Big Brother 5

14.6m Americans voted in the primaries that were held on this year's Super Tuesday

62m Votes were cast for President Bush in the last presidential election. Mr Bush and John Kerry won more votes than any candidate in US history

8.3m Estimated number of televotes cast during the Eurovision Song Contest last year

Source: Times archives

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