NEW YORK—Sure, Madonna may have scandalized the Vatican and shocked nearly every parent in America at some point during her long and provocative career full of shrewd image transformations.

But as the Material Girl hits the half-century mark this weekend, she may be stepping into a role that even she, with all her marketing savvy, might not have dreamed up: poster child for the 50-and-fabulous set.

Who cares about those recent tabloid headlines linking her to the Yankees’ A-Rod, or that tell-all book by her brother? Many women of a certain age look at Madonna and see a wonderfully fit, stylish, vigorous woman who’s made a fortune based on smarts, talent and ambition—no “Blond Ambition” puns, please—and just keeps on going. Her latest world tour, “Sticky & Sweet,” kicks off in Wales a week after her Aug. 16 birthday.

Talk about your New 50.

“I just think she’s awesome,” says Dale Lieberman, a 55-year-old mother of two grown daughters who works at a Marleton, N.J., dress shop and seemingly shares little with Madonna, save their age demographic. Yet Lieberman thinks Madonna is a great example of what 50 can be like these days.

“Here’s a woman that’s successful, takes care of herself, looks amazing—and she took the steps to get there. It doesn’t happen unless you take charge. She’s a great role model for many, many women.”

And if Madonna has any qualms about reaching this milestone—she isn’t speaking publicly about it—Lieberman wants to reassure her: It’ll be just fine. In fact, better than fine.

“When I was in my 30s, 50 just seemed so ancient to me,” says Lieberman. Now, she says, her kids are both out in the world. She exercises regularly for the first time in her life. She’s weeded out the unsatisfying relationships in favor of the truly genuine ones, enjoys nature, and loves to travel with her husband (they’re planning a trip to the Amazon next.) “Sometimes it’s scary how happy and fulfilled I feel,” says Lieberman.

That’s good news not just for Madonna, but for all the others reaching 50 in 2008—and some famous names pop up. Michael Jackson and Prince are two of the most discussed. But there’s also Ellen DeGeneres, Sharon Stone, Christiane Amanpour. Alec Baldwin, Viggo Mortensen. Andie MacDowell, Jamie Lee Curtis, original “Sex and the City” columnist Candace Bushnell. Michelle Pfeiffer, Annette Bening, Prince Albert of Monaco. And, linking them together as in one of those “Six-Degrees-of-Kevin-Bacon” trivia games: Kevin Bacon.

Madonna’s milestone should inspire men as well as women, says David Zinczenko, editor in chief of Men’s Health magazine. “I was in high school when she hit it big,” says Zinczenko, who’s in his late 30s. “Now that her first young fans are in their 30s, we look at Madonna as sort of a harbinger of the future for us. And the future looks pretty good.”