ONE, TWO, THREEEEEE!

Lauren Patton, 18, and Heaven Winand, 17, are floating in this sea of hormones wearing matching "Future Mrs. Joe Jonas" shirts.

"He's unbelievably hot," Winand says. This seems to be at the core of the JoBro appeal, though the friends from Perry Hall, Md., say there's also the music itself.

"I'm more of a metalhead, but I just love the Jonas Brothers," Winand says. "All of my friends think I'm insane."

She adds: "Their songs are really good, and they're understandable for our age group. They're about your first love, someone leaving you, just having fun and being young."

What the JoBro-slagging music critics don't know, the little girls understand -- though Rolling Stone did just award "A Little Bit Longer" four stars out of five, calling it "as assured as any American rock album released in 2008" and declaring the brothers the messiahs of power pop. ("We were shocked," Nick says about the review. "I thought they had the wrong band.")

Anyway, the JoBromance runs deep: Patton and Winand both have Jonas Brothers bedsheets and Joe Jonas dolls, plus Joe Jonas pillowcases, which means they wake up with him every morning.

The Jonas Brothers are the biggest deal in the massive if fickle kiddie-pop market, but they're not necessarily breaking ground: The tradition of young girls losing their minds en masse for dreamy young male singers is older than rock-and-roll itself, dating back to at least the 1940s, when the bobby-soxers swooned over Frank Sinatra. On the teen-idol continuum since then: everybody from Elvis Presley, the Beatles and that little kid who fronted the Jackson 5, to Leif Garrett, New Kids on the Block, the Backstreet Boys and Chris Brown.

"And I was really into Andy Gibb -- I had him on my pillow," says Jen Batchelder. She has come to the concert from the Eastern Shore with a group of young girls, including her 9-year-old daughter, Peyton. Mom totally gets the appeal. "I like their songs, and those boys were raised right."

This, too, is part of the JoBro pitch: their squeaky-clean image as purity-ring-wearing Christians who don't write lascivious lyrics, don't drink, don't smoke, don't swear and say they won't be having sex until they're married. They're perfect for the Disney demographic, though that perceived perfection is certain to bring intense scrutiny, with backlash just a misstep away. (Just ask Miley Cyrus, the Disney star and Vanity Fair cover girl who may be or have been Nick's girlfriend.)

"We're not saying we're perfect," Nick says. "We make mistakes. We're just trying to be the best we can be. . . . What's important is staying grounded." Though it's a bit like trying to ground a dirigible, isn't it?

The brothers are in the inner-sanctum of their dressing room now, tending to that time-honored pre-concert ritual of doing not very much at all. It's not exactly silent in here, but it's close -- and that's a strange thing to hear in the airspace around the Jonas Brothers.

But more than 12,000 girls are outside, though, just waiting to wail.

The shrill isn't even close to being gone.