A huge bodyguard stood outside the door to Victoria Beckham’s palatial suite at the Waldorf Towers hotel in New York early last week. Inside, a tightly controlled group of the most influential players in the world of fashion were being shown her debut line of 18 dresses. Only those considered high profile enough were admitted. Those stuck outside grumbled at the “control freakery” of Beckham and predicted a critical panning for the clothes.

Yet as the chosen few emerged, there was only one response, and it was a shocking one: “It’s good – really good.”

Shocking indeed. Beckham’s critical success at New York’s fashion shows was the biggest talking point of the week.

She had arrived in typical fashion, in a flurry of fake tan and flashing cameras, sporting a new, attention-grabbing cropped haircut that evoked positive comparisons with Audrey Hepburn. On her arm was her latest A-list new best friend, the actress and singer Jennifer Lopez. So far, so insubstantial.

Her collection changed everything. “We all went in expecting it to be awful, but she was tactile, passionate and seemed really genuine,” said one fashion director. “I got the impression she has worked really hard. To sit there and do what she did, to present to us lot, that takes a hell of a lot of confidence. I didn’t just like the clothes, I came out thinking she was a nice person.”

Inside the suite, Beckham had talked through every piece in the collection, describing her reasons for each detail, fabric, structure and stitch. Word was she became a bit nervy when questions veered away from the script, but the fashionistas were convinced by her ability to talk and her unwavering enthusiasm. Yes, there have been the odd snipes at her accent and her overfondness for the word “classy” for the audience’s refined tastes, but still, last week in Manhattan, you were hard pushed to find a word against her clothing range.

The highest praise came from Sophia Neophitou, the influential stylist and editor-in-chief of the cutting-edge magazine 10. “I loved it,” she said. “You know, I even ordered a piece for myself.”

According to her spokeswoman, Beckham was “excited” and “humbled” by the response. Privately she will be recalling those who have mocked her since she left the Spice Girls as a little more than a failed singer, clothes horse, wife to a famous footballer and mother to their children. At last she seems to have moved out of the shadow of Posh Spice. So how did she do it?

IN July last year the Beckhams arrived in Los Angeles to fanfare and great expectation. David was the man who was going to turn soccer into a mainstream sport in America. Victoria would bring up their three boys, Brooklyn, Romeo and Cruz, but also pursue other projects in the biggest market in the world. Brand Beckham, sullied by his affair with Rebecca Loos, would be saved.

Almost immediately, however, it started to look dodgy. They picked the wrong people to introduce them to Hollywood society in Tom Cruise and his wife Katie Holmes. A-list movie stars they may be, but their association with the Church of Scientology is increasingly regarded with suspicion.

On the football pitch, David was plagued by injury and his games for LA Galaxy were no more than reasonably well attended. Victoria’s foray into reality TV bombed. She hoped to set herself up as a player on the celebrity circuit and an influential figure worth watching with a six-part series called Coming to America on NBC. The show eventually aired as a one-hour special, which was widely mocked for featuring actors in what was supposed to be a documentary. To add insult to injury, nobody watched it.

“The Beckhams are the biggest disappointments in Hollywood,” said one LA insider. “The Cruise association is a terrible one. Add to that, Hollywood women need to be able to do two things – dress up and dress down – and she just can’t let it all hang out, which makes Angelinos tense. There are shared cultural rules here, and she breaks them by not chillin’.”

Earlier this summer there were stories that her jeans and sunglasses line was dropped from Kitson, a boutique on Robertson Boulevard where all the young hot starlets get snapped shopping, as much of a red carpet moment as any awards ceremony. Sales were poor, apparently, and she did not make enough personal appearances, according to the owner, Fraser Ross. In the end it turned out that all had been dropped was her menswear denim line.

Every now and again she would change her hair, which always seems to get a rise from the blogosphere and the women’s weekly rags, but in terms of high-class star quality and value, it appeared the Beckham brand was running near enough on empty.

Yet while she was not shining in Los Angeles, Beckham and her svengali-like manager, Simon Fuller, who masterminded the Spice Girls and now runs the Beckhams’ nonfootballing interests, realised she appealed to a wider community.

To a lot of women, she is a fashion icon. Her stand-by-your-man post-Loos decision may not have appealed to feminist instincts, but it chimed with the kind of woman who perhaps doesn’t have the balls, money or inclination to give an adulterous husband his marching orders. And many women love her style.

Johanna Waterous, a former retail sector director for the consultancy firm McKinsey and now a serial investor in emerging fashion brands, said: “If you head out of London and you stop 25 girls in the high street and ask them who they want to dress like, most of them will say her.” Even fierce old Germaine Greer has described her as “the Damien Hirst of dress wearing . . . she knows what to wear and how to wear it”.

For the sort of woman who thinks Kate Moss or Agyness Deyn look scruffy or weird, Beckham’s extremely groomed, clean-cut looks are more identifiably appealing than a more cutting-edge style. What better way to revive her fortunes than by exploiting this status through her own line?

Naturally many have questioned quite how involved Beckham was in the creation of her collection. They point to Fuller’s financial support of Roland Mouret, a French designer of accessible dresses similar to those produced by Beckham, as the guiding hand. Yet insiders insist that, while Mouret had an influence, the former Spice Girl’s vast wardrobe and experience of wearing clothes proved enough for her to take charge of the design process.

Working out of a small atelier with four staff based near her management’s offices in Battersea, south London, she had worked via e-mail, conference call and in person on the collection with the expertise of a project manager and pattern cutter, keeping control over the fabrics used and the detailing.

Even if she had outsourced the design to somebody else, Beckham remains the prime architect of what looks like a sure-fire success. In New York the influential buyers from top department stores were lining up to say how the collection will fly off the shelves.

Cindy Ho, fashion director of Villa Moda, the most influential boutique chain in the Middle East, said: “The collection is just great. All the styles are in saleable design.” Others praised dresses that will appeal to “a wider cross section of women than the usual catwalk offerings”. Perhaps most gratifying for Beckham were the plaudits from Bergdorf Goodman, the elite New York department store. “Victoria developed a collection that was as sharp and sexy as she is,” said Linda Fargo, its fashion director. “We feel that our customers will respond with the same enthusiasm we did.”

Not only did Beckham wow the buyers with the designs but her and Fuller’s commercial acumen has shone through. Only 400 of each dress in the first collection will be made and these will sell at prices ranging from £650 to £1,900. Such rarity will give them a collectable value. Fashion analysts in New York described them as “something to buy to keep for the children”. Elle Macpherson, the supermodel turned lingerie entrepreneur, said: “She’s a very clever woman.” For Beckham it is a triumph of tenacity. She has undoubtedly worked harder than most to break into the fashion scene and acknowledged as much last week. “I’ve been working on this for 34 years,” she said. “I always wanted to be a fashion designer. Then along came the Spice Girls which opened a lot of doors for me. And, let’s be honest, closed a lot. But those days are over. I was never going to be the world’s best singer, but I hope I can be a good designer.”

Mark Frith, the former editor of the celebrity magazine Heat, detects an element of vulnerability in Beckham’s desire for success. “I feel it’s important to her to be accepted and not be derided in fashion,” he said. “What propels her is the awkward teen she was. She wants to move away from that. I’ve always found her fun, with an incredible zest for life, but people see her coming out of restaurants not smiling and don’t see that side of her.”

He also notes that, almost despite themselves, many people feel an attachment to the couple, who have lived their adult lives as stars in the celebrity age. “For me the world of celebrity started with that photograph of them both wearing black polo necks and looking really shy when they got engaged,” he said. “We saw her getting married, exchanging vows – we couldn’t help but feel involved and attached.”

Even critics are finding themselves won over. Kelly Cutrone, an American PR maven, said: “To my mind, she hasn’t done much except be Victoria Beckham. At times it has seemed she is so insubstantial, it’s almost like she’s a holographic projection. But still, she has star presence, and she seems to be getting away with it. You have got to give her props for that unstoppable strategic force – it’s a pretty balls out way to go.”

Talking of balls, perhaps the greatest irony of her success in New York was that it came at the very moment that David Beckham saw his stratospheric career enter its end-game. Last week, as she was accepting the plaudits in America, he sat forlornly on the England team’s substitutes’ bench as Theo Walcott, a 19-year-old who plays in his position, scored a hat-trick. “I don’t expect to play every game anymore,” said Beckham afterwards. Handily, his wife is finally winning hers.

Additional reporting: John Harlow in Los Angeles

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