With the London summer Olympics just 100 days away, advertisers hope that social media will do much of the heavy lifting in raising brand profiles, by getting consumers to chat about promotions online.

Big consumer brands have long seen the Olympic Games as a way to get more consumers to buy their products. This year, several are thinking of them as a way to talk up their brands on Facebook - which of course could lead to even more purchases.

The games run from July 27 to August 12 this year.

"Back in 2008, it was very much about paid media," said Mark Renshaw, chief innovation officer at Leo Burnett, a unit of No. 3 advertising agency Publicis, referring to the last summer Olympics. "Now the reason they want to have a relationship (with consumers) is to generate shared media."

That's in part because of the sheer amount of time people are spending on social media. By the end of last year, some 794 million people visited Facebook each month, and each spent an average of 377 minutes — more than 6 hours — on the site, according to comScore Inc.

In 2008, Facebook had just 145 million users. Online marketing then focused on building websites, Renshaw said. Today, brands are building elaborate campaigns partly designed to create a buzz on Facebook and other social media sites such as Pinterest and Twitter.

Take Samsung Electronics, which recently launched its U.S. Olympic Genome Project. It uses a game called "How Olympic Are You?" to establish people's connections to the Olympics, such as finding athletes from their hometowns, or athletes who like the same music or movies they do.

It gathers the information by tying in to a user's Facebook page. The game dangles prizes such as discounted electronics and a trip to the Olympics to keep consumers coming back; whenever consumers complete an activity, such as a quiz on Olympic trivia, they are invited to post results to their Facebook page.

Facebook "is where consumers are," said Ralph Santana, chief marketing officer of Samsung. "If you can figure out how to build communities around your brand, it's really powerful."

Consumers are spending about 8 minutes per visit, on average, on the "How Olympic Are You?" site, Santana said. That is about double the time they spend on ordinary Samsung sites.

Social media "drives us toward content that is able to provoke consumer conversation," said James Eadie, Olympic portfolio director for Coca-Cola Co. "That drives longevity."

Coke's Olympic gambit is its "Move to the Beat" campaign based on a song created by DJ Mark Ronson and singer Katy B. Fans can collect beat fragments on Facebook and edit a version of the song for their own page.

Procter & Gamble this week unveiled its "Thank You Mom" advertisement showing mothers around the world raising Olympic athletes. Marc Pritchard, P&G's global marketing and brand building officer, is hoping online viewers will "like" the video on Facebook and drive traffic to its own Facebook pages for brands like Tide detergent, Pampers diapers, Oil of Olay moisturizers, and Cover Girl cosmetics.

"What we want to try to do is get a 10 percent lift on our Facebook brand pages," he said, meaning P&G hopes to add 5 million to its fan base of 50 million over the next few months. "That would be a lot quicker than we normally do."

Most brands are developing ways to calculate what each click of the "like" or "share" button is worth, Renshaw said, based on factors such as how many people saw it, engaged with it, and the total spent on a particular campaign.

Digital media spending by London 2012 sponsors amounts to 15-20 percent of budgets, Leo Burnett says, with digital outlets attracting funds that might have gone to television in prior years.

None of the brand representatives interviewed for this article would provide advertising spending estimates for their Olympic campaigns. But ad executives said a comprehensive multimedia Olympic campaign might cost anywhere from $30 million to $50 million.

The pricetag is worth it, brand executives said, because they believe they can weave tighter connections between their brands and target customers during the Olympics compared to other events. P&G's Pritchard said recalls of messages after the company's Vancouver 2010 Olympics television campaign was 30 percent more than for its regular campaigns.

(Reporting By Sarah McBride; Editing by Richard Chang)

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