NEW YORK - If you're expecting to be shocked by all the Super Bowl ads, don't hold your breath: There won't be many surprises.

About 20 of the roughly 36 Super Bowl advertisers put their TV commercials online before today's broadcast. That's a major shift: It's up from last year when only a handful of companies released their ads before the game.

Acura put out its spot showing talk show host Jay Leno zooming off in a jet pack. Actor John Stamos already can be seen getting bonked in the head in a Dannon ad. And tens of thousands have viewed Victoria's Secret model Adriana Lima in a Teleflora commercial.

Why the flurry of pre-releases? The Super Bowl is advertisers' biggest stage, with 111 million-plus fans expected to tune in. But after paying an average of $3.5 million for 30 seconds, advertisers are eager to stand out in the crowded field of about 70 Super Bowl commercials. Companies figure what better way to do that than to generate buzz online. But does it pay to show all your cards, err, ads?

"It's creating 'pre love' for your spot," says Greg DiNoto, chief creative officer of advertising agency Deutsch in New York. "Advertisers are creating an armed camp of habituated enthusiasts."

Advertisers are taking their cue from Volkswagen. The German automaker took a risk last year by releasing its Super Bowl ad for its redesigned 2012 Passat sedan that features a young boy in a Darth Vader costume before the game aired. The gamble paid off and the ad quickly became a viral hit on video-sharing website YouTube, with 49.4 million views since.

The ad also helped boost sales of the Passat: The sedan went on sale in the summer and has been a popular seller for Volkswagen in the U.S. In December, for example, volume sales of the car more than doubled to nearly 23,000 for the year.

This year, marketers are hoping to make a big splash by releasing their ads early, too. Careerbuilder.com's chimps are back for the eighth time, as is E*Trade's baby who's making his fifth appearance. One Chevrolet spot has an end-of-the world scenario. And a vampire party is cut short by bright LED headlights on an Audi in an ad for the automaker.

So far, the two most talked about pre-released spots are by carmakers. Honda's CR-V ad starring Matthew Broderick in a grown-up version of his 1986 movie "Ferris Bueller's Day Off" has 10.2 million views.

Volkswagen's teaser ad - one that's not actually going to air during the Super Bowl - shows dogs barking "The Imperial March." The ad, with 11.2 million views, has been more popular than the actual Super Bowl ad, which shows a dog losing weight to chase a Beetle. It had had 2.1 million views.

Releasing the spots early is a way for advertisers to engage people where they spend a lot of their time these days - online. Indeed, about two-thirds of smartphone and tablet computer users check their devices while they watch TV, according to research firm Nielsen. The ads can also make people feel like they're in the "know."

"People feel like they have a horse in the race if they find a commercial they like before the Super Bowl," said Barbara Lippert, curator of popular culture at ad agency Goodby, Silverstein & Partners in San Francisco, which worked on three Chevy spots for the Super Bowl. "They feel like an insider when they finally see it."

But with so many pre-released ads this year, the strategy could backfire, said Raymond Taylor, a professor of marketing at the Villanova School of Business in Villanova, Pa.

For instance, he says Honda's Acura ad that shows comedians Jay Leno and Jerry Seinfeld competing for the first Acura NSX sports car might have gotten more buzz if it hadn't been released early. The ad, which has gotten 10.8 million views, includes little touches like a cameo from the "Soup Nazi" from the "Seinfeld" sitcom.

"Releasing the ad early takes away the element of surprise and reduces the possibility of a real 'wow' factor during the game," Taylor says.

Best Buy wanted to preserve the surprise factor of its spot, so it decided to only release details about its ad - not the ad itself. The features superstars in the tech world who invented everything from the camera phone to mobile game app Words with Friends.

"It's the one moment that you have an audience of that scale and proportion that will give you 30 seconds to talk about you're brand and what you're doing," said Drew Panayiotou, a Best Buy senior vice president. "You can't find that anywhere."