Perhaps most important as the president’s team struggles to put his campaign back on track is a renewed effort to win the three remaining debates, starting with Thursday’s face-off between Vice President Joseph R. Biden Jr. and Representative Paul D. Ryan. Mr. Biden began traveling to a Delaware hotel on Sunday for three days of debate camp.
Under the tutelage of David Axelrod, the president’s chief strategist who is personally overseeing the preparations, Mr. Biden will be counseled on how to avoid Mr. Obama’s mistakes and even correct them with a more aggressive prosecution of the Republican ticket. Mr. Axelrod’s involvement highlights the stakes the Obama campaign places on the debate, and Mr. Biden has been reading “Young Guns,” the book co-written by Mr. Ryan, and practicing attack lines that Mr. Obama avoided.
The focus on Mr. Biden comes as the campaign tries to diagnose what went wrong in Denver and what to do about it. Advisers had seen two presidents during practice debates, one who had been listless and passive two nights before and another energetic and aggressive the next night. It turned out the former was the one who showed up in Denver. He kept looking down and was not using the lines they had practiced assailing Mitt Romney, who kept the president on the defensive and presented a forceful case against his re-election.
For Mr. Obama, it was arguably the lowest point in his campaign for a second term. The campaign’s own focus groups and research indicated that he lost. Mr. Obama did not fully realize as he walked off the stage just how badly it had gone, but aides said he resolved to step up his game. “He doesn’t brood — he acts,” Mr. Axelrod said. “Whatever the concerns were about yesterday, he wakes up the next day ready to take it on again.”
On the conference call convened by aides in Denver and Chicago even as the candidates were still on stage, there was no debate in the Obama campaign about the debate. None of the advisers fooled themselves into thinking it was anything but a disaster. Instead, they scrambled for ways to recover. They resolved to go after Mr. Romney with a post-debate assault on his truthfulness. Ad makers were ordered to work all night to produce an attack ad. And they would seize on Mr. Romney’s vow to cut financing for Big Bird.
Mr. Obama has been helped by two subsequent events. A labor report on Friday showed that unemployment had dropped to 7.8 percent from 8.1 percent, still historically high but back down to where it was when he took office. And his campaign privately spread the word that fund-raising had soared, giving him a bankroll for a comeback attempt.
But the debate remains a singular event in the life of the campaign, watched by more than 67 million people — a larger audience than for any of Mr. Obama’s 2008 debates, either of his nominating conventions or any of his State of the Union addresses.
Thursday’s debate between Mr. Biden and Mr. Ryan may not draw quite the same audience, but both sides view it as critical and are preparing for a contentious clash. “With Paul Ryan, it’s a different dynamic” than when he debated Sarah Palin in 2008, said Jennifer Granholm, a former Michigan governor who played Ms. Palin in debate practice then. The vice president “can go hard on policy.”
In rehearsals, Representative Chris Van Hollen, a Maryland Democrat who is playing Mr. Ryan, has mimicked what he considered the Republican’s staccato speaking style and penchant for slashing arguments wrapped in a smile. “I expect the vice president to come at me like a cannonball,” Mr. Ryan told The Weekly Standard.
Mr. Biden’s advisers view Mr. Ryan as a walking encyclopedia of numbers and policy and hope he might get lost in the weeds. “The key is to be able to cut through the numbers that often don’t make sense,” said Mr. Van Hollen. Also crucial is helping Mr. Biden tame his own loquacious nature and proclivity for gaffes.
The Obama-Biden team approached the debate knowing the perils. History showed that incumbents tended to lose their first debate, both because of their own confidence and the chance for a challenger to appear as an equal to a sitting president.
Like other presidents, Mr. Obama’s debate preparations were hindered by his day job, his practice sessions often canceled or truncated because of events, advisers said. One session took place just after he addressed a service for the four Americans slain in Libya, leaving him distracted.
Mr. Obama does not like debates to begin with, aides have long said, viewing them as media-driven gamesmanship. He did not do all that well in 2008 but benefited from Senator John McCain’s grumpy performances. Mr. Obama made clear to advisers that he was not happy about debating Mr. Romney, whom he views with disdain. It was something to endure, rather than an opportunity, aides said.
Senator John Kerry of Massachusetts was recruited to play Mr. Romney. The preparation team was kept small. The most important players were Mr. Axelrod; David Plouffe, the president’s senior adviser; and Anita Dunn, a former White House communications director. Others included Joel Benenson, the president’s pollster; Ronald A. Klain, Mr. Biden’s former chief of staff; and Robert Barnett, a longtime Democratic debate coach.
By the time Mr. Obama retreated to Nevada for a final couple days of practice, the debate prep team was getting by on as little as three hours of sleep a night as they crafted answers and attack lines. Mr. Kerry played a range of Mr. Romneys — aggressive, laid back, hard-edge conservative — and got in the president’s face, according to people in the room. Mr. Obama’s alternating performances left aides walking off Air Force One in Denver looking worried.
On stage, Mr. Obama seemed thrown off as Mr. Romney emphasized elements of his agenda that seemed more moderate and was surprised that the moderator, Jim Lehrer of PBS, did not pose more pointed questions. The president’s team had decided in advance not to raise Mr. Romney’s tenure at Bain Capital, aides said, but Mr. Obama held back on other attack lines they had intended to use. The base wanted him “to gut Romney,” one adviser said, but swing voters hate that and he was seeking a balance. Few thought he found it.
Joining the damage-control conference call were Mr. Axelrod, Mr. Plouffe, Jim Messina, the campaign manager, and Stephanie Cutter, his deputy, in Denver; and Ms. Dunn, Dan Pfeiffer, the White House communications director, and Larry Grisolano, a political adviser, in Chicago. In just minutes, they reversed a longstanding strategic decision; at the start of the campaign they had decided to attack Mr. Romney as a committed conservative rather than a flip-flopper, but now they decided to use his debate statements to argue that he was reinventing himself.
Mr. Obama walked off the stage thinking he at least had gotten in some of his points. “This was a terrific debate,” he said in the closing minutes.
“He knew that Romney had had a decent night as well,” Mr. Axelrod said later. “But it’s very hard when you’re standing there. It’s hard when you’re up there to judge it completely.”
Mr. Obama’s advisers were so off balance that they did not show up in the media filing center for the traditional post-debate spin until long after the Republicans. But they were relieved that at least there was no single memorable moment to be used against Mr. Obama in an ad. And they took some solace from focus groups showing that he broke even with Mr. Romney on substance even if he lost over all.
By morning, the Democrats had an ad criticizing Mr. Romney. They had scheduled a morning rally and were surprised that the Romney team had not. As they watched Twitter and some of the entertainment shows on television, they noticed a lot of attention on Mr. Romney’s pledge to cut money for public broadcasting, so they added a line to Mr. Obama’s speech and dispatched a volunteer in a Big Bird costume to a Romney event.
The president proved as aggressive in his post-debate rallies as he was passive in the debate, but the campaign was besieged by anxious Democrats. Mr. Messina had to pep up a demoralized staff in Chicago. Mr. Obama took the blame during calls with advisers. “This is on me,” he told them. Asked by some if Mr. Kerry was at fault, Mr. Obama said no. “It wasn’t Kerry,” he sad. “Kerry was fine.”
Beyond the vice-presidential debate, Mr. Obama is focused on his next encounter with Mr. Romney, on Oct. 16; lines unused in Denver may finally be aired in Long Island. But for a hypercompetitive politician, the first debate remains a raw subject. Asked if Mr. Obama was making fun of his performance, one adviser said, “We’re not at that point yet.”
This article has been revised to reflect the following correction:
Correction: October 8, 2012
An earlier version of this article stated incorrectly that Vice President Joseph R. Biden Jr. was moving into a Delaware hotel for three days of debate preparations. He will actually spend the nights at his home in Wilmington. Because of an editing error, an earlier version of a picture caption with this article misstated the time frame of Mr. Biden’s visit to Boca Raton, Fla. He was there in late September, not on Sunday, Oct. 7.
Original article on The New York Times