There is almost nothing about Adele’s single “Rolling in the Deep” or its accompanying video that would suggest the makings of a pop behemoth.

For one, the song’s retro, bluesy sound is a far cry from most of today’s club music inspired R&B from Rihanna and Bruno Mars.

For another, the woman singing it has ginger colored hair often styled in a retro Dusty Springfield-inspired bouffant. Though she is, in her way, quite beautiful, she’s far from sample size, looking nothing like Britney Spears, Beyoncé, or many of the other pop stars who have dominated the charts in the last decade.

Yet for the last two weeks, Adele’s sophomore album 21, propelled by this song of love and loss, has been the No. 1 album in America, selling more than 500,000 copies, a feat practically unheard of in today’s world of digital piracy.

Meanwhile, on Billboard’s Hot 100 chart, the woman running the show is the let-your-freak-flag-fly-high queen Lady Gaga. Her latest single “ Born This Way” is an intended anthem for America’s struggling gay youth and anyone who feels picked on for being an outsider.

The combined success of 21 and “Born This Way” represent a milestone in female pop music—a moment when the loner girls, who were ignored, overthrow the prom queens and take back the crown.

And it’s not a two-woman army, either.

Susan Boyle, a Scottish singer who earned international acclaim at the age of 48 when she appeared on Britain’s Got Talent, is another breakout star whose unconventional looks played a part in her popularity. When she had a makeover in August 2009, those who fell in love with the homely homebody almost had a collective breakdown.

La Roux, an electropop duo featuring Elly Jackson—an androgynous girl with a penchant for bright orange lipstick and an equally bright red, windblown Flock of Seagulls hairstyle—recently sold 2 million copies of their single, “Bulletproof.”

Size 28 Beth Ditto, the openly gay female singer of the indie rock band Gossip, has become a favorite on the ever fascistic style scene, singing at store openings for Alexander McQueen, opening shows for Jean-Paul Gaultier, and appearing in fashion magazines all over the world. The 30 year old also has a major label with Sony.

As does Sia, 35, another performer in an open relationship with a woman, who appears in her video as a construction worker. The Australian singer-songwriter has a blond bob that looks like a child’s doll after it’s been dragged around the playground.

And then there’s Janelle Monáe, who is on tour with Prince. The 25 year old has a traditionally beautiful face that would be the envy of virtually any woman, but she frames it in Cab Calloway-like drag.

Is fat the new thin? Is ugly the new beautiful? Is out the new in?

Even the pop starlets that embody conventional ideals of beauty appear to be throwing on ever more extreme outfits, donning outré head-pieces and sporting clothing that is far more theatrical than in years past, as if to point out that they will not be defined solely by their sexiness.

“You have Katy Perry wearing bright blue wigs and Ke$ha with the smears of paint all over her face, and Rihanna with her big red unruly blop of hair,” explained Maura Johnston, the founding editor of music industry blog Idolator and writer at Popdust. “I don’t think you would have seen something that wild 10 years ago in the initial wake of the Britney/Christina [Aguilera] boom. Even Selena Gomez, who’s this Disney princess, just dropped a single about how she’s not pretty enough and doesn’t conform to the beauty ideal.”

Annabel Tollman, a prominent celebrity stylist whose clients have included Shakira and Scarlett Johansson, has also noticed the trend. “When I’m talking to new artists who I’m working with, people are much bolder about their outfit choices. Gaga gets referenced a lot. She’s changed the landscape.”

Still, Tollman says the shift by no means began or ended with the "Poker Face" star. “Five pretty girls in mini-skirts are not going to sell a record anymore,” she said, in what sounds like a veiled swipe at The Pussycat Dolls. “We had so much of that manufactured pop and people are over it. They want to see real talent.”

The changing physical appearances of today’s female musicians could also be attributed to shifting economic realities. Stars like The Pussycat Dolls and Britney Spears, with their pricey glam squads, super-producers, and troupes of backup dancers, are a ridiculously expensive proposition in an era where consumers are buying fewer and fewer records. Last fall, Sony dropped Jennifer Lopez and her stratospheric beauty costs were cited by insiders as one of the major impediments of doing business with her.

By contrast, the women who put on their own eyeliner and dress themselves seem far more likely to write and produce their own music. Many of them even came from independent record labels, honing their talent and their looks in obscurity before garnering partnerships with companies like Sony and Universal. Though the bulk of them are not yet selling to the degree that Spears or Beyoncé did, their profits come in more consistently.

Robyn, for example, a rough-looking Swedish electropop singer with a mop of short blond hair (think: Annie Lennox by way of Scandinavia), went from being a 1997 teen star in the Britney Spears vein to doing edgier dance music on an independent label she founded called Konichiwa to getting a deal in the United States with Sony BMG. Not coincidentally, her biggest song to date, 2010’s “Dancing on my Own,” is about being an outsider, the story of the unseen girl in the corner watching the homecoming queen kiss the guy she wants. The lonely dance hit propelled Robyn from nightclub gigs to selling out Radio City Music Hall last month.

And Gossip, which features Beth Ditto, spent seven years on a small label called K Records, before being discovered by legendary producer Rick Rubin and getting signed to Sony.

But the trend of the rising underdog is not all powerful. Ron Shapiro, an independent music manager and former head of Atlantic Records, noted that country queen Taylor Swift is anything but jolie laide and she’s one of the bestselling artists in America today. Still, Swift writes her own songs, which also tap into rejection—even if those snubs are coming from Joe Jonas or John Mayer.

Nevertheless, Shapiro was relieved that Adele had become such a mainstream success. “The voice is extraordinary, the art and songs and the presentation are authentic… She’s so painfully real, and that does let you escape having to be a beauty queen in the traditional sense… And clearly, millions of people in the world feel the same way.”

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Jacob Bernstein is a senior reporter at The Daily Beast. He has also written for New York magazine, Paper, and The Huffington Post.