New York ? Late-night TV hosts returned to the air Wednesday after a two-month hiatus, showing support for their striking writers, plenty of creative stretch marks – and at least two scruffy beards.

David Letterman walked onstage amid dancing girls holding picket signs. His writers are back on the job, but NBC’s Jay Leno and Conan O’Brien and ABC’s Jimmy Kimmel returned without theirs.

Leno, however, offered a monologue that included jokes he said he had crafted beforehand. Whether that violated rules of the striking Writers Guild of America – to which Leno belongs – was not immediately clear. The union said Wednesday it was withholding comment until it spoke to Leno about his show.

Guests on the shows included two presidential candidates – with the Democrat, Hillary Clinton, sticking to Letterman’s union-sanctioned “Late Show” while Republican Mike Huckabee ventured across picket lines at Leno’s “Tonight.”

The biggest celebrity guest, Robin Williams, appeared with Letterman, while Leno welcomed chef Emeril Lagasse and rapper Chingy.

Filler was immediately evident on the shows without writers. O’Brien, sporting facial growth to match his red hair, showed off Christmas cards, danced on his table as his band played the Clash’s “The Magnificent Seven” and tried to see how long he could spin his wedding ring on his desk. Leno took questions from his audience.

There was also plenty of free on-air promotion for the guild’s cause. “The writers are correct, by the way. I’m a writer … I’m on the side of the writers,” Leno said.

“I want to make this clear. I support their cause,” O’Brien said. “These are very talented, very creative people who work extremely hard. I believe what they’re asking for is fair.”

Letterman, who had grown a mostly white beard, brought writers on to recite a top 10 list of their strike demands. They included “complimentary tote bag with next insulting contract offer” and “Hazard pay for breaking up fights on ‘The View.'”

“You’re watching the only show on the air that has jokes written by union writers,” Letterman said. “I hear you at home thinking to yourself, ‘This crap is written?'”

Williams teased Letterman unmercifully about his beard, alternately comparing him to Gen. Robert E. Lee, a rabbi and an Iraqi mullah.

On the eve of the Iowa caucus, presidential politics intruded: Huckabee appeared on Leno despite his apparent confusion about the strike and a bid by picketers to keep him away, and Clinton taped a cameo introducing Letterman.

“Dave has been off the air for eight long weeks because of the writers strike,” she said. “Tonight, he’s back. Oh well, all good things come to an end.”

Huckabee said he supports the writers and did not think he would be crossing a picket line, because he believed the writers had made an agreement to allow late-night shows on the air. But that’s not the case with Leno; “Huckabee is a scab,” read one picket sign outside Leno’s Burbank, Calif., studio.

The writers guild urged Huckabee not to cross their picket line. But Huckabee did, even showing off his electric guitar playing with Leno’s band.

“Huckabee claims he didn’t know,” chief union negotiator John Bowman said. “I don’t know what that means in terms of trusting him as a future president.”