Place your bets on the Super Bowl outcome now: Will post-game chatter center around Peyton Manning’s arm and the Chicago Bears’ defense? Or will office water-coolers be abuzz about who’s a better advertising pitchman—beer-stealing crabs or Britney Spears’ ex-husband?

It may be too early to tell who will win their respective grid-iron battles, but companies behind this year’s Super Bowl campaigns are banking millions of dollars that viewers be talking more about their TV ads than the performance of the Indianapolis Colts quarterback. Companies have paid an estimated $2.6 million per 30-second spot to have their commercial run on February 4, during Super Bowl XLI. The theory behind the big-money ad buy is that Super Bowl viewers pay as much attention to the splashy commercials as they do to end zone antics.

And despite the fact that the return on advertising expense is notoriously difficult to measure, finance execs who signed off on ads for this year’s game say that the unique nature of Super Bowl advertising and its supporting hype make it far easier to hold their marketers accountable for results.

The perennial advertisers are back, including Pepsi, Doritos, Taco Bell, and Anheuser-Busch—whose ad features thirsty crustaceans this year. Those stalwarts use the advertisements mainly to pump up the profile of their well-established products and generate brand buzz. Other companies that have run sporadic Super Sunday ads, such as Nationwide Insurance, will likely be testing the strength of their ads by monitoring website traffic. Nationwide, for example, will be able to tell whether Spears’ ex-husband Kevin Federline, who stars in the insurer’s commercial, drives viewers to the company website in the days following the Super Bowl.

Similarly, smaller companies, like domain registration company GoDaddy.com, are betting that its ad will help at least a portion of the 90 million Super Bowl viewers remember the company on Monday morning. “If the ad is good and creative and it drives Web traffic, then it will give the ad a longer return on investment than short-term sales of snacks or beer,” says Thomas Harpointner, CEO of Web services firm AIS Media.

GoDaddy.com, which has built awareness for its brand by running racy ads featuring the “GoDaddy Girl,” also plans to measure market share to gauge the success of its Super Bowl campaign, says CFO Michael Zimmerman. The company’s market share among domain registration companies increased from 16 percent after its first Super Bowl ad ran in 2005, to 32 percent when its ad ran during the 2006 football classic. The company also tracks “share-of-voice” numbers for the Super Bowl, which is a measure of media coverage following Sunday’s game. In 2005, GoDaddy received more than half of the total share-of-voice compared to other commercials, according to Bacon’s Multivision, which tracks this type of information.

While GoDaddy executives considered the company to be a success two years ago, “people just didn’t know who we were,” Zimmerman told CFO.com. “We needed to have more brand awareness, and one good channel to do that is television. Our CEO Bob Parsons said, ‘What better way to kick off an awareness campaign than the Super Bowl?'”

At the same time, GoDaddy and other Super Bowl advertisers have learned that the Sunday night broadcast is more than a one-shot deal. To widen the reach of their campaigns, businesses have created marketing tie-ins to the Super Bowl ads by increasing interactive features on their websites, running contests, sending out press releases about the commercials, and even buying TV spots that preview the ads. In addition, many companies plan to post the commercials on their websites Sunday night, hoping that by Monday morning other sites—including blogs, YouTube, and iFilm—will have snatched up the ads and distributed them to a wider Internet audience.

The CFO of direct marketing company InfoUSA, a newcomer to Super Bowl Sunday, has a clear metric to determine whether their gamble worked. “We have figured out we need to have about 750 new subscribers as a result [of the ad] to make our money back,” Stormy Dean told CFO.com. “We think that’s an attainable goal.” On Sunday, InfoUSA will run four ads promoting its new sales-lead product, Salesgenie.com. Dean estimates the entire campaign, with one ad running during the first quarter and the others to air during the pre-game and post-game events, cost the company about $3.5 million.

Because of the hefty price tag, Dean found himself more involved in the decision-making process than in other marketing campaigns. “Since it was a big lump sum kind of payment, it was something that everybody in senior management got involved in to make the decision,” he says. The pre-game publicity has already paid off for InfoUSA, says Dean. More than a week before the game, Salesgenie.com has garnered national media exposure, including a mention of the ad in USA Today, and now CFO.com. “You’re able to generate a lot of buzz for a long time, for more than the 30 seconds during the game,” Dean says.

Super Bowl veteran CareerBuilder.com has taken that pre-buzz marketing a step further by running teaser ads in the weeks before the Super Bowl, including ads that will run during the third and fourth quarters of the game. The campaign will culminate in a commercial that puts an end to the chimpanzees who made their debut during a 2005 Super Bowl ad, and became popular for torturing their one human coworker with bubble wrap and laser pointers. (“Watch the CareerBuilder ads evolve. Feb. 4 on the big game,” the ad tagline reads.) The Sunday commercials will kick-start a new campaign with an “it’s a jungle out there” theme to encourage employees sick of their jobs to visit its site.

The Super Bowl ads set the tone for the company’s branding campaign for the year, even though they make up a small part of CareerBuilder’s $250-million marketing budget, says CFO Kevin Knapp. “We go through rigorous hard metrics as well as anecdotal evidence to make sure the return from marketing, including the Super Bowl, is effective,” he told CFO.com. There’s proof that the game-day ads worked for CareerBuilder: After last year’s Super Bowl, CareerBuilder saw a 30 percent increase in the number of people going directly to the job search site. The company also credits the Super Bowl with part of the reason it surpassed the revenue of its competitor Monster.com in North America last year.

With return-on-investment easier to measure when a Web component is involved, there’s been less emphasis on brand recognition and more on accountability, AIS’s Harpointner adds. “For CFOs, the clickthroughs on websites gives them measurable results,” he says. “Marketers are forced to be more accountable.”