The temperature outside was barely above freezing, but Lawrence H. Summers was walking eagerly, almost rhapsodically, into Loeb House just about an hour after sunrise on Jan. 10. He looked fresh, buoyant, assured. And he was early, a significant feat for the oft-tardy Harvard president.

Summers had good cause for his confident stride. The year just past had been, by all accounts, his most successful since taking office in 2001. The turbulence of his early tenure had subsided. His critics lay dormant. And as Summers prepared to meet with fellow members of the University’s top governing board, his bosses were pleased.

Inside Loeb House, the monthly gathering of the Harvard Corporation was unequivocally positive, according to two University officials who were later briefed on the meeting. The agenda sported the usual array of topics: the undergraduate curricular review, ongoing plans for expansion into Allston, and the University’s multi-billion-dollar capital campaign—key items that were sure to define the next decade or longer with Summers at the helm.

The Corporation had high expectations for their president, whom they had charged four years ago with a mandate to “shake things up,” as one former Corporation member said in an interview last week. And as they departed their January meeting, the University’s most powerful leaders were as optimistic as ever, the officials said. Harvard’s future lay ahead.

Just four days later, Summers would speak at a now-infamous conference at the National Bureau of Economic Research. He would attempt to explain the scarcity of women on elite science faculties. He would use the phrase “intrinsic aptitude.” And, suddenly, the future was on hold.

The phone was ringing constantly at the desk of James R. Houghton ’58, senior fellow of the Corporation, as news of Summers’ remarks first emerged, recalled an employee in Houghton’s office who refused to give his name. Harvard insiders were surely curious to gauge Houghton’s reaction to the faculty uproar, which was then only beginning to gain momentum. Would he lead the Corporation in defense of the besieged president?

From his offices in upstate New York, Houghton serves as chairman of two mighty corporations: Corning, Inc., the $23 billion technology firm, and Harvard University, the $27 billion institution of higher learning. (He’s also chairman of the Metropolitan Museum of Art and a director at MetLife and ExxonMobil, among other high-powered projects.)

Houghton, who earned $5.6 million last year at Corning, is paid nothing for his service to Harvard, but his influence over the world’s most prestigious university is boundless. Several individuals close to members of the Corporation, including their friends and former Harvard officials, say that as the board’s most senior member, Houghton effectively exercises veto or approval power over nearly every major decision at the University. His support would be essential if the president were to survive the growing drumbeat of criticism.

And as emboldened professors began raising the specter of Summers’ resignation, attention on campus turned increasingly to the seven-member Corporation, the only group with the power to unseat the president. It seemed an unlikely outcome, and yet as the situation continued to deteriorate, the board would have to respond.

Of his six colleagues on the Corporation, Summers could easily count on the backing of two whose reputations at Harvard are inextricably tied to his own: Robert E. Rubin ’60, Summers’ predecessor at the U.S. Treasury, and Hanna H. Gray, former president of the University of Chicago.

In early 2001, when members of the presidential search committee expressed concern over Summers’ “sometimes abrasive” demeanor, the outsider Rubin was enlisted to convince them otherwise, according to two former Harvard officials familiar with the search. Summers had long ago ditched his propensity to offend, Rubin told them.

And when a seat on the Corporation opened up in the first year of Summers’ presidency, Rubin was selected to fill it.

Gray, who will step down from the Corporation at the end of this month, was widely seen as Summers’ strongest supporter on the search committee. “Hanna, I think, saw some of herself in Larry,” said a former member of the Board of Overseers, the larger and less powerful of Harvard’s two governing boards.