In the fall of 2008, as Sen. Joe Biden pondered the delicate task of debating Gov. Sarah Palin, his debate team honchos circulated an internal preparation memo.
The first sentence: "No candidate for president or vice president in the history of the country has had more advice on what to say than Sen. Biden has on his debate with Sarah Palin."
Biden's then chief of staff Ted Kaufman, who's been friends with Biden for 40 years and was a part of that debate prep, recalled the line to CNN.
"And it's absolutely true," Kaufman said of Palin, then the governor of Alaska and a popular yet polarizing politician mostly unknown on the national stage. "Everybody had an idea about how to deal with Sarah Palin. And I think most of it wasn't the issues. It was more of just how do you deal with her because she is so unique.
"Most people felt it was just different and difficult to debate her."
On Thursday in Danville, Kentucky, Biden's debate team will have no such worries.
In the first and only face-off between the vice president and the congressman who wants his job -- Republican vice presidential nominee Rep. Paul Ryan -- advisers say Biden will be free to do what he does best: draw sharp contrasts and, perhaps, throw sharp elbows against a well-known conservative star.
A successful performance by Biden could reverse negative headlines and chatter aimed at the Obama campaign following the first debate between the president and challenger Mitt Romney.
It could also provide an Aha! moment for Biden supporters who have long argued the vice president's usefulness on the ticket and temporarily silence critics who key in on his gaffes. Biden's effectiveness in recent visits to Republican battlegrounds -- a clear attempt to pick off conservative votes -- could also prove his political worth.
Yet both tasks are risky. Experts agree that Biden is notably disciplined in high-stakes debates and his appeal can keep the race close in some traditional red states and red counties of swing states. But others note that missteps could cut deep.
"Normally with Biden, by his reputation, whenever he has a high-profile speaking engagement he has to tone it down. Because he has this reputation for gaffes," said Eitan Hersh, an assistant professor of political science at Yale University and an expert on campaign strategy.
"And here, he can't really do that because he needs to be really motivated and enthusiastic and the opposite of lethargic."
"It's not like the Sarah Palin situation. There you had the age and experience gap plus the male-female," said Alan Schroeder, a professor at Northeastern University. "I think having two men on the stage does liberate Biden a lot compared to 2008. But anytime you go up against someone who is junior to you, in age and experience, you have to be careful not to condescend."
After a widely panned performance by President Obama in his first debate with Romney, many Democratic supporters, journalists and even Republicans will watch to see how much Biden goes on the attack to make up for the president's admitted missed opportunity.
"Biden has a lot more pressure on him now than if, in fact, President Obama had even done a decent job," said Paula McClain, dean of Duke University's graduate school and a professor of political science. "I don't think anyone can argue that [Obama] blew a tremendous opportunity."
"He cannot duplicate that," echoed Lynn Vavreck, an associate political science professor at UCLA and co-author of the book, "The Gamble: Choice and Chance in the 2012 Presidential Election."
His advisers explained Biden's goal -- and opportunity.
"The vice president has never been shy about contrast," a campaign official said. "And he's never been shy about laying out...two fundamentally different visions for this country. He and the president are moving the country forward. He and the president believe that the Romney-Ryan agenda would bring us back to the failed policies that [hurt] our economy."
Helping Biden sharpen the contrasts in debate camp over the last few days in Wilmington, Delaware, are Kaufman; Ron Klain, another former chief of staff to Biden; Obama campaign senior adviser David Axelrod; and long-time adviser Mike Donilon, among others.
"He's been watching recent interview and speech footage of Ryan," the campaign official said. "He's talking to policy specialists about different topics.
"These guys are both good debaters," the official said. "They're both experienced guys. Paul Ryan's been the face of Republican policies for a long time. And the Ryan budget is the congressional blueprint for moving forward. For six years he's been the top Republican on the budget committee and his grasp for policy is second to none.
"Ryan's in a little bit of a box. Will he stand by the extreme positions that he and Romney hold? Or does he deny them and sort of deny their existence as Romney did the other night?"
Kaufman echoed the sentiment. "One of the hard things about preparing for a debate with Congressman Ryan is that you just don't know what positions he's going to take," Kaufman said.
"You've got to prepare for two or three different Ryans based on which Ryan, you know, shows up."
Since last week's debate, Democrats have cast Romney as a political chameleon attempting to change from red conservative to purple moderate.