By Michael Osborn BBC News entertainment reporter

Model Sophie Anderton was one of the lesser known celebrities

The fourth series of I'm A Celebrity...Get Me Out Of Here has provided plenty of entertainment for millions of fans around the country - but has it run out of steam?

The programme has been on our screens for the second time this year, and audiences have not proved as healthy.

The opening episode of series three attracted 10.1 million viewers, while audiences for the nightly show this time have hovered around the eight million mark.

More than 14 million viewers witnessed Kerry McFadden become queen of the jungle last time - leaving the climax of series four with a hard act to follow.

'Most successful'

But ITV say they are not disheartened with the show's performance - and are already promising that it will be back.

"It's by far and away the most successful reality show on British television, and we are not disappointed with the figures," said a spokeswoman for the network.

"The show has taken viewers away from other channels, and advertisers have not said they're disappointed," she added.

I'm A Celebrity sustains interest during its run with daily newspaper coverage, but this time around big stories like the David Blunkett affair have kicked it off the front pages.

Janet Street-Porter's spats with Paul Burrell were closely watched

Only the Daily Mirror splashed the show on its cover ahead of Monday night's grand finale.

It is a format that relies on famous faces being put through their paces around the clock.

Perhaps the latest crop of celebrities have simply not been well-known enough to command prominent column inches.

Fran Cosgrave was a relative unknown but in compensation there were two tabloid-friendly models in Sophie Anderton and Nancy Sorrell.

Criticism

"There was some criticism of Fran, but he went on to reach the final," said the ITV spokeswoman.

Yet the identity of older contestants Antonio Fargas and Sheila Ferguson would have tested the knowledge of youthful viewers, with 16-34 year olds forming the show's target audience.

The two singers in the camp whose chart history seemed quite distant - Brian Harvey and Natalie Appleton - decided to leave of their own volition.

The former All Saint's failure to endure five Bushtucker Trails did not provide very engaging television, although her suffering was engineered with the viewers' backing.

Unassuming panto star Joe Pasquale, with his refusal to be drawn into any jungle spats, was always the hot favourite to waltz off with the title.

Kerry McFadden (right) won the third series of the show

Viewers were left with the love-hate relationship between former Royal butler Paul Burrell and journalist Janet Street-Porter to see sparks regularly flying.

During the last series, the start of a romance between model Jordan and singer Peter Andre was a draw for audiences, but none of this series' line-up paired off.

I'm A Celebrity charted new territory during this series by bringing a surprise new contestant into the jungle.

Comic Vic Reeves' short-lived contribution was a week in the jungle with his wife and competitor Nancy Sorrell, but this ploy has been seen before on other reality shows.

The third series of I'm A Celebrity has been called a "phenomenon" by the show's makers - so the follow-up had a lot to live up to.

The show's audience may have slipped for a number of reasons, but its makers are sufficiently confident to save it from the axe.