Political cartoonist Herblock, who celebrated an important birthday yesterday, stepped out of an elevator in The Washington Post's lobby and into a jampacked surprise party hosted by Post Publisher Donald Graham and his mother, Katharine. Mrs. Graham told the crowd: "I have a special reason to be thankful to Herb. Without him, I'd be the oldest thing at The Post, now that Don has finally replaced the presses." We could tell you how old Herblock is, but then we'd have to kill you.

Have Pecs, Will Travel

The fabulous Fabio phoned us from Beverly Hills yesterday (okay, we phoned him first) and confided that he really wants to settle down and marry soon. He's just looking for the right woman. "I don't believe in divorce. In that way, I'm still old-fashioned," the 38-year-old Italian hunk told us. 'My mom said to me, don't ever get married if you don't find the perfect person.' To me, it's for life. Before I take that step, I want to be 100 percent sure."

Fabio, who has graced hundreds of romance-novel covers and even written a couple himself, said he's more interested in a woman's soul than her looks. "Beauty and everything will vanish with age," he said. "I just want a good, good person. That's the only thing that's going to get you through the bad times."

Until Cupid strikes, Fabio is busy. He'll be in town Saturday--along with his parents, visiting from Italy, beauty-queen mom Flora and engineer dad Sauro--for the National Italian American Foundation's annual dinner. He's still the pitchman for "I Can't Believe It's Not Butter" and is also starring in a new animated cartoon about the Norse god Thor. And despite all those nice sentiments about the unimportance of looks, he's working hard to keep his 6-foot-3, 225-pound body--50-inch chest, 32-inch waist, 19-inch arms--in shape. Dirt-biking is his particular obsession. "It's the most amazing aerobic exercise. You're wet when you're done, you're so sweaty."

Saturday will be Fabio's first trip to the States since March, when a goose smacked his face while he rode a roller coaster at Busch Gardens. Fabio has recovered from the encounter, but he hasn't been back on a coaster. "Come on, everyone can go on a roller coaster," he told us. "You want a thrill, jump on the back of my bike, I'll give you a thrill."

THIS JUST IN . . .

* Already coping with her husband's Alzheimer's disease and the fallout from Edmund Morris's loopy presidential biography, 78-year-old Nancy Reagan has broken some ribs at her Bel Air, Calif., home. According to her former press secretary Sheila Tate, Mrs. Reagan was retrieving some photographs from her basement last Friday when she walked into a piece of exercise equipment and slipped to the floor. "For a while she couldn't even breathe," Tate told us yesterday. "The doctor told her that it will be eight to 10 days before the pain starts to subside and a six-to-eight-week healing process."

* Hillary Rodham Clinton take note: Our friend Grover Norquist, president of Americans for Tax Reform, has instituted a pioneering employee health care program at his right-wing think tank. "As an alternative to dental coverage, our policy is that if anybody wants to get body-piercing or tattoos, we'll pick up the tab," Norquist told us yesterday. So receptionist Kate Meerstein, a 22-year-old Penn State grad who was hired three months ago, got her bellybutton pierced at Fatty's Custom Tattooz, and Norquist, good as his word, paid the $50 fee.

* If Marilyn Monroe were alive today, would she be running for president, too? "She was never a dumb blonde. . . . It was part of Marilyn's psyche that she wanted to excel," Hollywood producer David Brown tells Barbara Walters on tomorrow's "20/20" in advance of an auction of Monroe's possessions. One of candidate Monroe's issues might have been sexual harassment in the workplace. "She would have the biggest sexual harassment suit in history," Brown says. "And many of the men who even dared do what they did to her would be in prison or broke." Still, Brown adds, "nobody held a gun to her head. It was despicable, horrible. But it got her someplace."

* The word on Mick Jagger: Can't live with him, can't live without him. Ex-wife Jerry Hall has let him move back into their London mansion so he can be close to their four children. But he has his own bedroom, Reuters reports.

* Lots of consternation in the political world over Vice President Gore's apparent attempt to withhold vital information--i.e., that his middle name is Arnold--from an inquisitive fifth-grader in Henderson, Nev. But Gore's press secretary, Chris Lehane, told us the entire affair has been blown out of proportion. "It's old news," Lehane said. "We released his middle name along with his tax returns."