The trio is strange enough–and certain to prompt serious eye-rolling over another celeb-backed cause–but stranger still and very amusing is the play-by-play of how they came together. The love story began, actually, with a wardrobe malfunction in the “green room” of the Ritz-Carlton Hotel in Laguna Niguel, California. Handler was relaxing back stage, after interviewing Arianna Huffington before a crowd of 400 women leaders and Buffett (the event’s only male speaker), when Steinem walked in to introduce herself. Handler noticed, at that moment,  that her ripped camisole left one cup of her bra entirely exposed to her lifelong role model. “The perfect intro to Gloria Steinem,” says Handler, recalling the wardrobe malfunction that turned out to be an ice-breaker. The two women hit it off instantly and quickly agreed that Buffett, of all the day’s speakers, had been the most interesting and provocative.

It was Steinem, typically, who prodded Handler to start a movement in support of the Buffett tax plan. “There are so many great ideas here, but we need action to come out of it,” said Steinem about the Summit. As she went on to riff passionately about the widening gap between rich and poor, Handler started emailing her Hollywood friends, including Reese Witherspoon, to ask if they would be willing to pay more taxes a la the Buffett Rule, in order to equalize the system.  “I can get the celebrity crowd,” she vowed to Steinem.

An hour later, at the Summit’s cocktail reception, Buffett heard about the movement and was particularly pleased to learn that his heroine was an instigator. “I remember seeing Gloria 40 years ago, giving a lecture at Creighton University. She blew me away,” Buffett said, noting that Steinem “expresses ideas forcefully without being obnoxious.” Over in a corner, Steinem was deep in conversation with Facebook COO Sheryl Sandberg. “Can we put a petition out in the hall tomorrow, for women to sign in support of the Buffett Rule?” Gloria asked as I walked up to them. “You could put it online,” quipped Sandberg, meaning it seriously.

Not much would have come of all this if Handler and Steinem had not made their way to Buffett’s dinner table that evening. “Oh, hello girls, I’m excited to see you,” the billionaire said to the power duo. Handler, a standup comic, steered the talk in a sexual direction (“I’m an older man,” said Buffett, playing along. “I’m 77,” replied Steinem flirtatiously). Before they left his table, Buffett directed his new advocates: “I’d love for you to get on board and spread the word.”

Since the Summit in early October, Steinem has been collecting supporters of the Buffett Rule on, “pardon the expression, my Facebook fan page,” she says. Steinem is asking for zip codes so she can send names of supporters to the appropriate people in Congress. She also talked up the Buffett Rule on Chelsea Lately, Handler’s late-night talk show on E! .

Handler, meanwhile, is Tweeting and urging her pals who have millions of Twitter followers (as she does) to Tweet about Buffett and his tax reform idea. Rosie O’Donnell is signed on. When Handler emailed her asking for help, Rosie replied: “yes I am in. let me know how I can help. Don’t u love knowing Gloria? She is better than Jesus.”

Who knows how far this will go? A lot of celebs won’t love the Buffett Rule, and many who sign on will look to dodge it with the aid of their accountants and lawyers. Nonetheless, Buffett is basking in this unexpected advocacy. “This is what I was hoping would happen,” he says. Since he’s not a TV watcher, he had never heard of Chelsea Handler before the Summit, but, he says, “I fell in love with her.” He adds, “Anything I can do to help her, with facts or backup materials, tell her to call me. Tell her I have an 800-number for her, straight to my office.”

Here’s Handler, on stage with me at the MPW Summit, sounding off on Buffett and taxes:

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