With the Academy Award nominations out this week, fashion designers are already jockeying to dress the stars for their big night. But rather than picking the Oscar winners, designers are asking another question: Who will be the most effective at getting viewers to buy the clothes they see on the red carpet?

Among this year's nominees, the 'best seller' award is likely to go to a nominee whom few in the fashion world are discussing: Sandra Bullock. At , a Los Angeles-based Web site that links red-carpet photos to stores that sell the looks, Ms. Bullock's one-shouldered Vivienne Westwood dress at the Golden Globes ranked among the top of all red-carpet appearances this year in inspiring viewers to 'click through' to retail sites.

One lesson: It isn't pure chic that moves clothes. 'For the most part, celebrities that drive sales aren't necessarily the ones that get nominated' for awards, says Lily Hollander, editorial director of . The 45-year-old Ms. Bullock is not high on chic lists, but her down-to-earth image mean millions of women relate to her.

By contrast, with her Best Actress Oscar nomination for 'An Education' this week, Carey Mulligan has dozens of fashion designers vying to lend her baubles and gowns for the Oscars. The young actress with the pixie haircut is known as a sophisticated dresser. 'Carey Mulligan will be the most watched on ,' says Hamish Bowles, Vogue's European editor at large, recalling a sparkling Prada dress the actress wore recently.

But despite Ms. Mulligan's fashion cred, she may not be the savviest choice for product placement. At , Ms. Mulligan is not one of the stars who moves the most viewers to buy clothes. Ms. Mulligan wasn't available to comment.

Celebrity placement is more voodoo than science, but among this year's nominees, other Oscar sales influencers may include plus-sized Gabourey Sidibe and the classic Meryl Streep. Ms. Sidibe, the star of 'Precious,' is 'an alternate paradigm for the red carpet, but she can carry these very strong colors,' says Mr. Bowles. What's more, the plus-sized market is one of fashion's fastest growing.

And Ms. Streep's maturity and demure style choices may appeal to women over 40, who spend more on fashion than other demographic groups.

Red carpets have become a primary marketing channel for fashion. The Academy Award nominees' photos will be plastered from Boise to Bombay after the March 7 awards show, which will be watched by something north of 35 million television viewers--and seen on a gazillion blogs. It's an irresistible advertising medium. In Los Angeles, designers employ VIP handlers, who work to get the designers' clothes on celebrities who might be photographed in them.

The fashion industry does this because it works. After Sienna Miller wore Thakoon's spring bustier jumper to the premiere of the fashion documentary 'The September Issue,' every store that bought the piece sold out, says a spokeswoman for designer Thakoon Panichgul.

Yet success, for a designer, is a delicate balance of star power and timing. After Jessica Alba presented an award at the People's Choice awards last month, her Burberry Prorsum knotted platform sandals generated the most click-throughs to retail sites of any red-carpet appearance this season on .

Unfortunately for Burberry, those spring-season shoes won't be available in stores for another month. So shoppers had to settle for similar looks offered on the site by Robert Clergerie and Callisto.

Nothing is too minor for mention. Stylist Mark Townsend announced that he set actress January Joness hair in a French twist for the Golden Globes, blow drying her hair 'with a round brush' and securing 'it with about 10 bobby pins.' He also named hair products and prices: Moroccanoil Treatment, $39 for 3.4 fl. oz.