The low TV ratings for the BCS championship between Alabama and LSU this season were one reason why college football conference commissioners proposed a four-team playoff. (Chris Graythen/GETTY IMAGES)

When the commissioners from the 11 Football Bowl Subdivision conferences and Notre Dame Athletic Director Jack Swarbrick announced Wednesday in Chicago that they had reached a consensus on a four-team college football playoff beginning in the 2014-15 season, nobody was in a better mood than Southeastern Conference Commissioner Mike Slive and ACC Commissioner John Swofford.

Four years after they presented their conference brethren with the first formal plan for a playoff and were basically laughed out of the room — “The conversation lasted about 10 minutes,” Swofford recalled — the power brokers of college football had finally agreed a playoff was the next logical step for the sport’s postseason.

But with the 12-member Bowl Championship Series presidential oversight committee set to meet in Washington on Tuesday to approve the proposed playoff, the question that will likely take center stage is why now, after more than 100 years of simply playing postseason bowls, is this the right path for college football?

Money certainly played a role. The BCS currently generates about $180 million from its television contract with ESPN, but some predict when negotiations on a new deal open this fall, a four-team playoff could be worth $400 million.

Bob Boland, the academic chair at New York University’s Tisch School of Sports Management, went one step further. He said once a playoff is established on the marketplace, the money from television rights fees and neutral site bidding of a national championship game could mirror that of “a second Super Bowl.”

But the answer university presidents are likely to get from the commissioners will be much simpler. After spending decades defending the parochial nature of college football to the public, the fans left college football’s decision makers with no other choice.

“Any system only can last so long without support and with just constant criticism,” said Big Ten Commissioner Jim Delany, one of the last major figures to come on board with a playoff. “The level of criticism was so significant over time that, in some ways, it forced the change. . . . The BCS never had any vocal supporters.”

20 years in the making

The way commissioners describe this new playoff model, it is simply the latest evolution for a sport that has been searching for a pragmatic way to declare a national champion for more than 20 years.

It started in 1992. The SEC, Big East, Big 8, the now-defunct Southwest Conference, the ACC, Notre Dame and six bowl games joined together to form the Bowl Coalition. In 1995 it was re-structured with just three bowl games and renamed the Bowl Alliance.

But neither incarnation could avoid controversy because the Big Ten and Pacific-10 were contractually obligated to participate in the Rose Bowl. So in 1998, the BCS was formed as a way to pair the No. 1 and No. 2 teams in a bowl game to determine the national champion.

The brainchild of then-SEC commissioner Roy Kramer, it brought the Rose Bowl into the rotation and ranked teams using a formula of human polls and computer rankings.

Over the years the system received adjustments, such as adding a separate BCS national championship game, changing the computer models used in order to de-emphasize margin of victory or adding the Harris Poll in 2006 after the voters in the Associated Press poll refused to be a component in the BCS formula any longer.

“We tweaked it, and the more we tweaked it, the less confidence we inspired,” Delany said this week.

Inclusion also became an issue.

In 2009, after watching both Boise State (2006-07) and Utah (2008-09) finish seasons undefeated but without a shot at the national championship, Utah Sen. Orrin Hatch called on the Justice Department to investigate whether the BCS violated anti-trust laws. Even President Obama got involved following his election in 2008, voicing support for a playoff system to determine the national champion instead of the BCS.

Whenever the system faced attacks, however, BCS supporters would point to how a playoff could diminish college football’s regular season.

But the final straw came this past season, when the national championship game rematch between LSU and Alabama produced the lowest overnight television rating of the BCS era, the exclamation point on a bowl season that saw television ratings for BCS games drop by 12 percent from the year before.

By the time commissioners from every FBS conference and Swarbrick met to discuss the postseason in January, “there was a recognition that we needed to make some changes to maintain the enthusiasm that’s been built through the years for college football,” Big 12 interim commissioner Chuck Neinas said.

“We had to recognize that to keep the public we had to do something.”

The biggest obstacles to a playoff came in the form of Delany and Pac-12 Commissioner Larry Scott, both of whom were adamant on maintaining the importance of the Rose Bowl. They preferred to keep the status quo or switch to a “plus-one” model that would pit two teams in a national championship game following the bowl season.

“We’re conservative by nature. We wanted to make sure things didn’t happen too quickly,” Delany said of the Big Ten. “I don’t think there’s any question we didn’t lead the parade.”

The key compromise that led to Wednesday’s historic announcement was the decision to propose a selection committee similar to the ones used in other NCAA sports, according to three people with direct knowledge of the negotiations. In addition, the commissioners also decided to rotate the semifinal games among existing bowl games.

It helped that because SEC teams have won the past six BCS national championships, Slive — not Delany — wielded the most power in the room this time around.

“I’m sure it won’t satisfy everyone,” Scott said. “Until you have an eight-team or 16-team seeded playoff, there will be folks out there that aren’t completely satisfied. We get that. But we’re trying to balance other important parties, like the value of the regular season, the bowls, the academic calendar.”

Will the presidents agree?

On Tuesday afternoon at a Dupont Circle hotel, the BCS Presidential Oversight Committee, chaired by Virginia Tech President Charles Steger, will meet for at least four hours to discuss the commissioners’ playoff proposal. For it to go into effect, the presidents must approve the model.

All 12 presidents have been kept abreast of developments in the negotiations, but the Big Ten’s representative, Nebraska Chancellor Harvey Perlman, told The Post on Thursday that he must still be convinced a playoff is best for college football.

Perlman will advocate on behalf of the plus-one format, but even he concedes that likely will be the minority opinion in the room. “I’ve been alone on this before,” he said.

The expectation is that the presidents will initially approve the playoff proposal but send the idea back to commissioners with further instructions for cleaning up details, like revenue sharing, that remain unresolved. Both Scott and Swofford said this week they would need unanimous approval, but Perlman noted the most important votes will come from the presidents of the “Big Five” — the SEC, Big Ten, Pac-12, Big 12 and ACC — because the commissioners have determined 79 of the 80 teams that would have been ranked in the top four the past 20 years came from one of those five conferences.

Perlman added the presidents would be reluctant to go against all the commissioners, who have spent more than 100 hours and at least seven formal meetings hashing out a playoff proposal over the past six months.

It’s this togetherness that has college football on the precipice of a playoff many fans have wanted for years.

“People change. Perceptions change,” Swofford said. “This is the most unified the commissioners have been, to be quite honest. There’s gonna be some criticism and controversy, but we’re beyond the point where there’s something that kills the deal.”