Uncle Bernie’s choice of material at a surprise appearance Friday night at a fundraiser for Democratic presidential candidate Barack Obama endured heckling and campaign rebuke.

Toward the end of a 10-minute standup routine at the Hyatt Regency Hotel in downtown Chicago, the 50-year-old star of “The Bernie Mac Show” joked about menopause, sexual infidelity and promiscuity, and used occasional crude language.

“My little nephew came to me and he said, ‘Uncle, what’s the difference between a hypothetical question and a realistic question?’” Mac said. “I said, I don’t know, but I said, ‘Go upstairs and ask your mother if she’d make love to the mailman for $50,000.’”

As the joke continued, the punchline evoked an angry response from at least one person in the audience, who said it was offensive to women.

“It’s not funny. Let’s get Barack on,” a man shouted from the crowd, which paid $2,300 each to support the Illinois senator.

About 15 minutes later, Obama tried to smooth things over with a joke of his own.

“We can’t afford to be divided by race. We can’t afford to be divided by region or by class and we can’t afford to be divided by gender, which by the way, that means, Bernie, you’ve got to clean up your act next time,” Obama said. “This is a family affair. By the way, I’m just messing with you, man.” [source]