The Giants' 17-14 upset win drew an average of 97.5 million viewers, according to A.C. Nielsen, topping the old record average of 94.1 million. That was set in Super Bowl XXX in 1996, when Dallas beat Pittsburgh 27-17.
Was it the pursuit of perfection or the rooting interest in the underdog? Probably, it was both. In any event, Sunday night's Super Bowl was the most-watched, ever, in terms of the number of viewers who watched at least six minutes of the broadcast, according to A.C. Nielsen.
Super Bowl XLII attracted 148.3 million total viewers, topping the old record of 144.4 million for Super Bowl XXXVIII in 2004, when New England beat Carolina 32-29 on a last-second field goal by Adam Vinatieri. (Total TV audience is defined as viewers watching the game for at least six minutes.)
While last night's game fell well short of the game's Nielsen ratings peak of 49.1 set in 1982, when the 49ers beat the Bengals, 26-21, in Super Bowl XVI, its 43.2 rating was the highest since Super Bowl XXXIV in 2000, when the Rams beat the Titans 23-16. (Ratings measure the portion of total TV households watching a program, as opposed to total numbers of viewers.)
"All the elements were there," said David Carter, executive director of the University of Southern California's Sports Business Institute, rattling off the factors: unbeaten Patriots, "name" quarterbacks and big media markets (No. 1 New York and No. 7 Boston, whose Patriots may have lost the game but whose Nielsens led all U.S. cities, with a 55.6 rating). "The more fragmented television has become, the more the remaining big events that combine sports and entertainment and drama has really driven interest."
The capping element was a gripping game. Super Bowl XLII began with a huge audience (the highest-rated first 30 minutes in eight years) that just kept building, to 105.7 million viewers between 9:30 and 10 p.m. ET, as the lead changed hands three times in the fourth quarter.
Who watched where?
Interestingly enough, New York City wasn't among the metropolitan areas most-glued to TV sets for the Giants' win, according to NFL numbers.
That made the championship thriller the second-most-watched show in American broadcast history, behind only the last episode of M*A*S*H in 1983. Some 63.9 million viewers then stayed tuned to watch confetti fly and speeches flow, making this the most-watched postgame show in 10 years.
Can next year's Super Bowl hope to put up these kinds of numbers? Probably not, says Robert Seidman, whose Web site, TVbythenumbers.com, tracks and analyzes Nielsen ratings.
"This matchup was special, in terms of history. The game went down to the wire, and the game still only did 5 to 6 percent better than last year," he says, referring to the Colts-Bears game whose audience was 93.2 million.
Seidman says it's amazing for any sports event to recapture or surpass audience levels of a decade or more ago, but in an age of declining ratings, "I'd be surprised if next year's game doesn't revert back to the levels of recent years."
John Helyar is a senior writer for ESPN.com and ESPN The Magazine. He previously covered the business of sports for The Wall Street Journal and Fortune magazine and is the author of "Lords of the Realm: The Real History of Baseball."