Companies including Coca-Cola, Mars and Nestle spent the past week trying to generate excitement for their ads. Anheuser-Busch InBev even hosted a viewing party aboard a cruise ship docked at a New York City pier, complete with escargot, duck and cheesecake.
Still, Super Bowl advertisers know the unexpected can happen. And when it does, they have to be ready.
One of the most memorable moments from last year's game, for example, was a tweet from Oreo. After a blackout hit the stadium, the company posted an image of an Oreo cloaked in darkness with the tagline "You can still dunk in the dark."
It got more than 10,000 retweets on Twitter within an hour.
The power of a traditional Super Bowl ad is nothing to sneeze at, of course, with companies shelling out an estimated $4 million for a 30-second spot. The price buys the eyeballs of the more than 100 million people who are expected to tune in.
Even for companies that release their ads on YouTube early, though, nobody really knows how they'll go over during the game. And Chrysler and Coca-Cola are among the companies keeping at least one of their spots under wraps.
Here's a peek at some highlights of tonight's Super Bowl ad action. Check back for updates throughout the night.