Never underestimate the power of Oprah.

Ten months after Tory Burch launched her clothing line in 2004, she got a call from the queen of daytime talk. Oprah Winfrey's producer had happened onto Burch's shop in Manhattan's Nolita district and bought an embroidered tunic as a holiday gift for her boss.

Winfrey liked it so much, she wore it on the cover of her magazine (published by Hearst, the Houston Chronicle's parent company), and invited Burch to appear on her show. Afterward, Burch's Web site received an astounding 8 million hits.

"A lot of our success is due to Oprah," the 40-year-old designer said before a recent appearance at Saks Fifth Avenue. "I say that flat out because it's true."

Even without Winfrey's stamp of approval, Burch likely would have become fashion's new "it girl" because she's got the goods.

In the past three years, the Burch look ¡ª one that combines country-club chic with exotic embroidery and bold prints ¡ª has flown out of stores. High on the list: Bell-sleeve tunics, ballet flats with Burch's "double T" logo, smart sheaths and "dickey" sweaters with removable cuffs and collars that recall an earlier era when stylish women like Audrey Hepburn, Ali McGraw and Jackie Kennedy reigned.

Burch has a lot to be happy about right now. In addition to her booming business, she has a new romantic interest: Lance Armstrong.

The seven-time Tour de France champ contacted Burch after reading a profile of her in the February issue of Vanity Fair magazine.

"He promised he had never done that before," she said, with a laugh. "I thought that was very bold of him."

They met over coffee and found they have a lot in common. For one thing, "he has twins, I have twins," she said. Since then, they have been seen regularly together.

On the night before her Saks appearance, Burch and Armstrong attended a party at the home of John and Becca Cason Thrash and ate dinner afterward at bistro moderne. Oddly enough, his ex, singer Sheryl Crow, was performing at the rodeo the same night.

The two women are strikingly similar physically ¡ª attractive blondes with toothy smiles and sunny personalities.

But are Burch and Armstong an item?

"I wouldn't go that far," she said, fumbling for words. "He's a good friend. He's a wonderful guy. We've been spending some time together. He's a really good person."

"He's part of our team," chipped in Samantha Gregory, the company's vice president of global communications.

Everyone laughed.

Burch is much more comforbable talking about her business. She is surprised at her runaway success, which she credits to hard work, good timing and a little luck.

"I design things I would like to wear," she said."I like a subtle sexiness to clothes. Women tell me when they wear (my designs) their husbands notice."

Another big reason for Burch's success: Her clothing has the look of designer wear but is priced within splurge level of an aspirational working-woman's budget. The giraffe print sleeveless shift Burch wears retails for $295; a classic polo goes for $95; a colorful tunic is $195.

"She had me at the first tunic," Melissa Milstead said while perusing the Tory Burch boutique at Saks in a "vintage" Burch purple blouse she bought two years ago after watching the Oprah episode.

"It's a dressy casual look, very ladylike and age appropriate," said the 40-something Milstead. "I don't wear Juicy (Couture). I've outgrown that."

But teens dig Tory, too. At the Thrash party, many Houston women showed up with their daughters. More than 300,000 pairs of Burch's "Reva" ballet flats, named for the designer's mother, have sold (at $195 a pop) since they were introduced last year ¡ª largely to teenagers and 20-something shoppers.

"Her audience ranges from high school kids to grandparents," said Jeanne Ruberti, director of the store's Fifth Avenue Club. "Her look is right for this kind of country-club gal."

Raised in a Philadelphia suburb, Burch was always impressed with her parent's sense of style. So when she started her own clothing line, she created timeless pieces based on her mother's vintage wardrobe.

"The first season I did a dickey at my mother's request. It was so great in the '60s and '70s; and it's been a great seller," she said. "Every season it sells incredibly well."

Burch had virtually no design experience but had been in the business for more than a decade. A former assistant fashion editor at Harper's Bazaar, she also worked in the public relations departments at Ralph Lauren, Vera Wang and Loewe (headed up by Narciso Rodriguez).

She dropped out of the fashion scene when she married venture capitalist Chris Burch in 1996 and almost immediately became pregnant. She had three sons (the twins, now 10, plus a 6-year old) and also helped to raise her husband's three daughters, now adults. And the couple were fixtures on the New York charity social scene nearly every night.

When Burch plunged back into fashion three years ago, more than a few eyes rolled. Her name is often preceded by "socialite" ¡ª a term she detests. (The pithy Web site socialiterank.com currently lists her No. 17 in New York's elite social set.)

While she jokingly refers to herself as a "socialite/designer," she admits her glamorous lifestyle has enhanced her business."Women across America are buying into what they believe our clothing represents," she said.

From the beginning, she envisioned a lifestyle company, offering beach towels, candles, umbrellas, handbags, jewelry and shoes as well as clothes ¡ª all in colorful surroundings. Her boutiques are painted her favorite colors ¡ª a bright Herm¨¨s-like burnt orange and lime green.

"I love interesting mixes of colors, gold prints and patterns. That's become a signature for us," she said.

Her spring and summer collections have a Safari theme, with animal prints and the bright colors worn by Masai tribes. They're also inspired by Turkish fishing villages, with crocheted pieces and colors of the Mediterranean sea. Most of her ideas come from photographs, since Burch can't find the time for overseas research.

Her Houston visit made her enthusiastic to open a freestanding boutique here as soon as she finds the right location.

"I like Texas women," she said. "They're unique. They definitely have a style, and they exude confidence. And they're happy. To me that's a big thing. I like happy people."

A self-described "perennial optimist," she said she was tested when she and her husband ¡ª who bankrolled her start-up and is the company CEO ¡ª separated. After some fractious discussions, they decided to continue their business partnership while working out details of their divorce.

"It was an incredibly tough year, and we got through it," she said. "For me, that's a milestone. I'm excited that we will be friends and business partners. At the end of the day, it's for our children."