Paul Ryan may be the first vice-presidential nominee who once prepped a veep nominee.

In late 1996, Ryan, then 26 years old, worked as a policy adviser for Jack Kemp, a former New York congressman and Bob Dole’s running mate. On the trail, Ryan guided Kemp as he prepared for his October debate with vice president Al Gore. The official prep sessions, however, were mostly a disaster. Kemp rarely practiced, and when he did, he lost his temper. At one mock debate, according to writer Robert Draper, Kemp “shot the bird” at Senator Judd Gregg, who was playing Gore, and stormed out of the room.

Once Kemp took the stage in St. Petersburg, Fla., he was hardly ready to challenge the Clinton-Gore record. He did not have an array of facts and figures memorized. Instead, he leaned on clunky anecdotes and platitudes. The entire exchange was tepid, and Kemp flopped, even in the eyes of his friends. “Within minutes it was apparent that Kemp was not prepared,” recalls Ed Gillespie, a Romney adviser, in his book Winning Right.

Ryan, of course, was a lowly Kemp aide, and it was not his responsibility to corral his gregarious boss. But 16 years later, as Ryan prepares for his own vice-presidential debate, his mentor’s stumbles are fresh in his mind. According to a Ryan insider, “Paul may be over preparing, just because he knows how important this is” — for the Romney campaign and for his reputation as the intellectual leader of the Republican party.

“Jack was a virtuoso and a genius, but he was not the most diligent student before the debate,” says Bill Bennett, a former education secretary who worked with both Kemp and Ryan in the early 1990s. “I remember Paul had these huge, loose-leaf binders he’d carry around. Afterward, he probably knew that it wasn’t a good night for Jack. But Paul is a different creature, a creature of habit and self-discipline, and I know he will be ready.”

For much of last week, Ryan was at Wintergreen, a sprawling resort in central Virginia. Under the shadow of the Blue Ridge Mountains, Ryan and his advisers quietly reviewed policy papers, held several mock debates, and kept distractions to a minimum. BlackBerries and iPhones were switched off, and Ryan avoided the traveling press.

Yet the Virginia sessions were not the beginning of Ryan’s prep for Thursday’s debate. Soon after the Tampa convention, Ryan convened his inner circle, which includes longtime aides such as Andy Speth and Romney hands such as Dan Senor, and asked them to compile briefing books, much like the binders he used to organize for Kemp. On the campaign plane and at his home in Janesville, Wis., Ryan has been constantly reading the policy books, using his favorite disposable blue pen to make changes.

By mid-September, Ryan had two large books with him at all times. One was for domestic policy and the other for foreign policy. Romney’s policy staff in Boston was helpful in providing information about Romney’s positions, but Ryan took it upon himself to write much of the analysis and talking points. By late September, Ryan, who often vacations in the Rocky Mountains, asked his staff to book him a few rooms at a mountain resort so he could prepare in relative silence and anonymity. The Romney campaign settled on a place in rural Virginia because Virginia is a swing state and its mountains are fairly accessible.