Ken Carson, always something of a stiff, is loosening up.

Friday is officially his 50th birthday, and the doll that defined boyish American urbanity is working on a comeback, proclaiming on billboards in Los Angeles and New York his love for Barbie. Critics raved about his appearance in Toy Story 3. And in a new reality TV show, Genuine Ken: The Search for the Great American Boyfriend, eight clean-cut real-life contestants vie to be judged worthy of Barbie: a guy with style who knows how to listen, cook, surf and spoil the material girl with displays of affection.

Mattel Inc.'s push to make Ken cool, particularly among adults, is part of a broader campaign to crank up sales of the doll as it hits the big 5-0, as the company did successfully when Barbie passed the half-century milestone two years ago. Mattel executives say they are relaxing their tight control over Barbie's and Ken's images because they missed marketing opportunities in the past by letting Ken -introduced to the world in March 1961 in red swim trunks, sandals and a yellow terry-cloth towel -turn into, well, a square.

"What we realized a few years ago was, 'Wait a second, there are people having more fun with the brand than we were,' " Stephanie Cota, Mattel's senior vice-president of global marketing for girls brands, said in an interview. "Part of the journey that we've been on is figuring out how to have fun with the Barbie brand without making fun (of it)."

Barbie has long been the alpha female. Sean McGowan, a toy analyst with Needham & Co., estimated that Ken makes up less than 10 per cent of the Barbie line's sales.

He said Ken's appearance in Toy Story 3 -where the doll shows up wearing short shorts, an open shirt and a blue ascot while tooling around in a pink convertible, seemingly oblivious to his main purpose to serve as arm candy for Barbie -could have backfired.

"Ken stole the show 'cause he's a clothes magnet," Mc-Gowan said. "That's risky, but it worked. He winds up looking cool. (But) that's a fine line between parody and pushing the envelope."

According to Barbie lore, she called it quits on her relationship with Ken in 2004, feeling that after 43 years, she needed time apart.

By producing a reality show à la The Bachelor and launching Facebook and Twitter accounts for Barbie and Ken, Mattel is targeting an older cohort than its core preschool and grade-school crowd.

The Genuine Ken reality series, which debuted last month on the online video website Hulu, was designed to appeal to 18-to-34-yearold women who fondly remember playing with their own Barbie and Ken dolls but who now watch the latest reality show vixens and villains for entertainment.

Hosted by MTV star Whitney Port, whose long blond hair and willowy figure echo classic Barbie traits, the series has been among the most popular reality shows on Hulu.

In one episode, the visuals shift into slow motion when the contestants jog to the beach and later rip off their shirts; the show zooms in on their well-sculpted abs. When one contestant strips naked to don a wetsuit, a turquoise "Ken" name tag appears onscreen to cover his anatomy.

The winner will be given the title "Genuine Ken: The Great American Boyfriend," and Mattel will produce a Ken doll in his likeness. The show was just one aspect of Mattel's makeover of the doll named after the late Ken Handler, the son of Mattel founders Ruth and Elliot Handler.

"Will Genuine Ken have a direct effect at retail? Probably not," Cota said. "But will Genuine Ken continue to help keep this brand relevant or leapfrog us into the next level of relevancy? Absolutely. We can't drive sales if we don't have a product and brand property that is relevant, modern, fresh and contemporary."