But what made ESPN such a force in college football was its growing role in the professional game.

Like most cable networks, ESPN draws revenue from two sources: advertising and subscriber fees. When it struck a deal with the N.F.L. in the late 1990s to carry a full season of games, that revenue stream became an ever-quickening cascade of cash. N.F.L. games, probably the most valuable commodity in televised sports, became the leverage that allowed ESPN to demand more money from cable companies, with fees nearly quadrupling in one seven-year period.

Today, nearly 100 million households pay about $5.54 a month for ESPN, regardless of whether the subscribers watch it or not, whether they realize it or not. This year, ESPN will take in more than $6 billion in subscriber fees.

The network’s revenue is such a boon to its parent company, Disney, that the former Disney chief executive Michael Eisner said in an interview: “To this day, the Walt Disney Company would not exist without ESPN. The protection of Mickey Mouse is ESPN.”

Flush with those cable fees, ESPN has gone on one of the biggest shopping sprees in TV history, securing the rights to prime college football for the next decade and more. It spent $2.2 billion for SEC rights through the 2023-24 season and in May announced a 20-year agreement with the SEC that will include building the conference’s own television network. In a 12-year, $7.3 billion deal, ESPN gained the rights to the college football playoff, which begins after the 2014 regular season.

The power of television contracts has driven the recent fever of conference switching, as colleges forsake geographic loyalties in pursuit of more lucrative deals. In the last year, three universities jumped to the Atlantic Coast Conference for all sports: Pittsburgh, Syracuse and Louisville, none of them located within 200 miles of the Atlantic coast. Each stands to receive more than $16 million a year from the A.C.C.’s $3.6 billion contract with ESPN.

In the world of big-time college sports, universities like these are the winners. But there are colleges on the losing end, too — those stuck in conferences whose value is diminished by realignment, those that simply lack the resources to build teams good enough to break into the exposure game.

David Schmidly has watched what he calls the “massive increase in commercialization” of college sports as the president of several universities, most recently New Mexico, a public college with a respected men’s basketball program but a mere trickle of television dollars. As he sees it, the escalating television deals, especially at a time when states are slashing subsidies to public universities, have only widened the gap between the haves and the have-nots — between a “group of super-wealthy institutions and those that are trying to gnaw at the wood of the doors to get in.”