Fusty senators and congressmen are gaping at this year’s under-dressed arrivals. Every summer 20,000 interns barely out of their teens report for unpaid duty as photocopiers, coffee makers and skivvies in America’s corridors of power. Gone are the days when they were an invisible army.

You can tell the newcomers by their Manolo Blahnik-style heels, says Beth H, 24, a former intern who is now a full-time congressional worker: “They all want to be Carrie Bradshaw of Sex and the City.”

The girls from the Midwest with helmet hair, pumps and blue eye shadow have been replaced by sexy sophisticates. “Washington is becoming more socially savvy,” Beth said. “It didn’t use to exist on the social map.”

Madeleine Albright, a secretary of state under Bill Clinton, is appalled by the bare flesh on parade in the capital. She told US News magazine that she had to stop herself from scolding girls who flashed their midriffs. “If you dress like a sex object you’ll be treated like one,” she said.

Lynn Jennings, of the Congressional Black Caucus, found placements for 44 interns in Congress this year. Style consultants were drafted in to advise them on professional dress etiquette. “We tell our interns that they’re not on the fashion runway,” she said. However, the message does not appear to be getting through.

Lindsey Marburger, 20, an intern at the Smithsonian Museum who wears a tank top, flowery skirt and flip-flops to work, said there were degrees of “hottitude”.

Her friends, both male and female, at the State Department dressed more squarely than congressional interns, and those at the White House were the biggest stuffed shirts. “The more important your boss, the more formal you are,” she said.

Yet it was Monica Lewinsky, the world’s most famous intern after her fling with Clinton, who may have contributed to the fall-off in standards.

Cathy Smith, 24, who at 16 was a “page” or schoolgirl intern in Congress and now studies at the London School of Economics along with Lewinsky, said: “I know a lot of people who fancy congressmen, but they didn’t use to become famous or get a book deal. She became such an icon that interns think they can become important as well.”

The new congressional intake is being egged on by Wonkette, a blog that recently ran a “Hotties on the Hill” contest. The winner was an intern called Stephanie, who friends say is a “total knock-out with a Julia Roberts smile”. Her nickname is Hungry Eyes.

For Marburger the new flaunt-it style is a sign that women have finally broken into a male-dominated world: “The 1990s generation tried to fit in with the boys’ club. Now it’s accepted that we have a right to be there and we can dress like girls.”

Not that the men mind. “The congressmen are loving it. They can’t get enough of it,” said Beth.

One intern said that her boss “definitely tried to look down my shirt yesterday. Tomorrow I’m buttoning up the blouse to the collar”.

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