NEW YORK (AP):

David Letterman's apologies to his wife and staff for having sex with co-workers meant another big night in the ratings for the late-night TV talk-show host.

The Nielsen Co overnight measurement of the 56 biggest United States markets netted Letterman's Late Show on CBS a 4.2 rating - higher than anything rival NBC had in prime time.

Nielsen didn't immediately have an estimate yesterday of the size of Letterman's audience. The overnight rating was slightly less than last Thursday's show, when 5.8 million people watched Letterman say he had been the victim of a US$2-million blackmail threat that led him to reveal he had sex with staff members.

As Letterman mixed wisecracks with contrition on Monday's show, he said his wife, Regina Lasko, had been "horribly hurt by my behaviour" and stated flat-out that those affairs "are in the past."

He vowed to repair his relationship with his wife, whom he married in March after 23 years of courting.

"Let me tell you folks, I got my work cut out for me," he said ruefully.

References

Monday's show was the first Letterman had taped since Thursday. While he laced the show with references to the scandal, only one other late-night host, Craig Ferguson, made any reference to it. Jay Leno, Jimmy Fallon and NBC's Saturday Night Live had all made jokes in earlier shows, but everyone but Ferguson, a Scottish comic, avoided the topic on their Monday night and yesterday morning shows.

As host of the Late Late Show, Ferguson follows Letterman's Late Show. Letterman is also his boss, since Letterman's production company, Worldwide Pants Inc, produces the Late Late Show.

"The person you work for, the person you admire and respect, is caught in an embarrassing situation," said Ferguson. "And your job is to be funny about that, while trying to keep your own job."

"So this is my last show," he joked.

Ferguson did make light of the situation, joking that it had now been revealed how he got the job in the first place.

But Ferguson defended Letterman, calling him "the king of late-night television."

"If we are now holding late-night talk-show hosts to the same moral accountability as we hold politicians or clergymen, I'm out," said Ferguson. "I'm gone."

Fall weather

On the Late Show, Letterman noted the cool fall weather, reporting, "It's chilly outside my house; chilly INSIDE my house."

Then he cautioned the audience, "This is only phase one of the scandal. Phase two: Next week I go on 'Oprah' and sob."

A bit later, guest Steve Martin gave Letterman his kidding consolation: "It proves that you're a human being. And we weren't really that sure before."

Martin Short, making an unannounced appearance, playfully plopped himself in Martin's lap.

"You spend one more minute on his lap, you're gonna get blackmailed," Letterman quipped.

During the hour, Letterman apologised to his staff, which, he said, had been subjected to "being browbeaten and humiliated" by reporters since his revelations.

"My thanks to the staff for, once again, putting up with something stupid I've gotten myself involved in," he said.