On Super Bowl Sunday a 30-second commercial during the nearly four-hour-long television broadcast can cost up to $4m...Back in 1967, when the Green Bay Packers of Wisconsin defeated the Kansas City Chiefs in Los Angeles, the TV audience for the first Super Bowl was split across two broadcasters, and 30 seconds of commercial time cost advertisers $42,000.

But professional football was fast becoming America’s favourite spectator sport and the National Football League and media companies realised the Super Bowl could be a different kind of sporting event. Unlike other American sports, such as baseball, a single game determines the ultimate winner in the NFL.

Recognizing its unique hold on public attention and potential for generating ad revenue, broadcasters began to pay huge fees for the rights to televise the games. Along with the NFL, they set about positioning the Super Bowl not simply as an athletic contest but also as a patriotic and cultural celebration. The half-time show, for instance, features world-famous entertainers, from Madonna last year to Beyoncé this weekend.

Last year, an estimated US TV audience of 159m tuned in to watch some portion of the game. Leslie Moonves, chief executive of US network CBS, which has the rights to broadcast this year’s matchup, describes the day as a “national holiday” in the US, a communal event rivalled only by Christmas and Thanksgiving. This weekend’s game in New Orleans, between the San Francisco 49ers and the Baltimore Ravens, is expected to draw record TV audiences.

“It doesn’t matter if you are from any state or any city, if you were born here or if you moved here. If you are Catholic, Protestant, Jewish or non-denominational. It is the one day where everybody in America has something really fun and in common that you share,” says Mark Waller, chief marketing officer of the NFL, with only a little hyperbole. “The Super Bowl is America’s great campfire.”

The Super Bowl is, of course, also a festival of consumerism on a massive scale. The National Retail Federation expects total spending on new TVs for viewing parties, snacks, decorations and Super Bowl clothing to reach $12.3bn this year. According to the greeting cards manufacturer Hallmark, which sells a range of football-themed greeting cards and decorations, Super Bowl Sunday is the top at-home party event of the year.

It’s also second only to Thanksgiving as the US’s biggest eating day. According to the National Chicken Council, an estimated 1.23bn chicken wings will be consumed in the US on Sunday – enough to stretch from San Francisco to Baltimore 27 times. Super Bowl Sunday is as much a contest between advertisers as it is a sporting competition.

This year, with CBS selling 30 seconds of commercial time for a record $4m, about $133,333 a second (nearly twice the rates charged a decade ago), a roster of Super Bowl veterans, such as Anheuser-Busch, PepsiCo, and Coca-Cola will line up against rookies including BlackBerry, SodaStream and Gildan Activewear.

For the advertisers whose spots stand out among the 60 or so commercials, the massive audience the Super Bowl delivers can help put the spotlight on a brand, introduce a little-known product to the masses, and spur sales. Merely announcing plans to advertise during the big game leads to a rise in the stock price for publicly traded companies, according to a researcher at the University of Colorado at Boulder.

It was in 1984, when Apple broadcast a commercial to introduce the Macintosh computer, that the Super Bowl spot began to assume bigger cultural significance. “1984” was a minute-long Ridley Scott-directed ad that nodded to George Orwell and ended with a beautiful blonde in orange shorts throwing a hammer at a giant screen that depicted an image of Big Brother.

The ad aired just once on daytime TV but attracted such attention that it was featured on news broadcasts and later screened in movie theaters. It also set off a race among advertisers to create cinematic ads that would entertain audiences as much as the Super Bowl itself.

And last year, according to the online measurement firm Visible Measures, Super Bowl ads were viewed online about 400m times, outstripping even the huge TV audience for the game. Many viewers, claim other researchers, are as interested in watching the commercials as the actual football game – and even in watching them again and voting for their favourites in various online polls afterwards...

...The 1985 Super Bowl saw the first “Million-Dollar Minute” in television, with ad rates for spots during the game rising ever since. Can the price keep going up? David Sable, global chief executive of the Young & Rubicam agency, says: “Everybody always asks [if there is a limit to the price of a Super Bowl ad], then they get more expensive. People [have woken] up to the fact that digital hasn’t killed television advertising. When it works together, it works really well.”

To justify the steep price tag, brands devote months to crafting campaigns. Today, there aren’t just Super Bowl ads; there are ads for Super Bowl ads. This year, for instance, about a dozen companies – including Coca-Cola, Tide, Volkswagen, Audi, Mercedes-Benz, as well as Taco Bell – have released online teasers.