Paul Ryan has a constant companion on the campaign trail -- a weighty burden he clearly can't live without.
It's an oversized, well-worn brown briefcase that holds about 40 pounds of paperwork that he's been studying nonstop to prepare for his debate with Vice President Joe Biden.
Ryan sat down for an exclusive interview with CNN to give some insight into how he is getting ready for his 90-minute face-off.
As he held the bulging briefcase in his lap, he told us that this is the way he has gotten ready for moments large and small his whole life: intense study.
"I do a lot of reading, that's what I've always done -- briefings and reading," Ryan said.
We asked Ryan about what one of his hunting partners told us about how he prepares to go after his prey, usually deer.
The friend said that before Ryan goes hunting he washes his clothes in unscented detergent, takes a shower with unscented soap and sprays unscented material on his boots -- all steps that hunters are known to take generally, but Ryan takes it to a completely different level.
"If you're into archery and bow hunting, that's the way to do it and be successful. I like the strategy of bow hunting and it takes a lot of preparation and I do take it seriously because I am much more successful if I do things properly and prepare the right way," Ryan said.
"I have always just believed that if you're going to do something, do it well."
How does Ryan's hunting prep mirror his debate prep?
"This stage is kind of new for me and I'm taking it very seriously," he replied. "I'm just doing my homework and studying the issues and I'll know he'll come and attack us. The problem he has is he has Barack Obama's record to run on."
Talk to anyone who knows Ryan well and they will use one word to describe him more than any other: prepared.
Ryan's older brother Tobin has been helping with his political career since he began his first congressional campaign in 1997 at age 27. He said Ryan has a "very heavy hand" in everything he does, and he has always been meticulous.
Tobin Ryan laughs at the huge stack of briefing papers Ryan carries around now -- a far cry from the way it was back in 1998 when he helped his brother get ready for his first debate as a candidate for Congress.
"I think we had about eight sheets of one-sided paper that listed out issues. I didn't really have to prepare Paul. It's never been an issue. This is a guy who absorbs more in a day than I think is humanly possible," Tobin Ryan said.
Steve King has been a close friend and political supporter since Ryan's first congressional run. He said Ryan, who sleeps on a cot in his congressional office in Washington, is known to be up studying briefing papers so late he often falls asleep face-first at his desk.
Debate prep partner 'immersed himself into being Joe Biden'
Ryan's countless hours of debate prep have consisted not just of reading and studying, but also role-playing with mock debates. Former Massachusetts Lt. Gov. Kerry Healey has been standing in as moderator Martha Raddatz. Ted Olson, the former solicitor general and renowned hard-charging litigator, has been playing the role of Biden.
Ryan said Olson has "immersed himself into being Joe Biden."
"I've done lots of mock debates with Ted. He's come to Janesville (Wisconsin), we've done debates there. We've done debates in hotels around the country where I am at the time," Ryan said. "We sit around a table, we have a moderator, and he and I debate each other. He (Olson) knows my record, he's studied it, he's studied what we do in Congress, arguments that the president and vice president use to try to win their debates by default."
A Republican source familiar with Ryan's prep tells CNN that while Olson has spent a lot of time going over lines and ideas with Ryan on the road, Ryan has also participated in half a dozen or more formal mock debates -- keeping the events to the 90-minute time as if they were the real thing.
The source said that for a while Olson would "break character" and dissect an answer with Ryan, but as the debate has gotten closer Olson has stayed in character and continued to pound away at Ryan as if he were Biden.
Tobin Ryan, who has been on the campaign trail a lot with his brother, has had a behind-the-scenes look at just how seriously the Ryan team has taken his debate prep.
"They carve out 30 minutes here, 45 minutes there, if possible two hours here. And if anyone encroaches on that time, you hear from people that you can't do that. Paul's got to do his reading."
As with most vice presidential running mates, Ryan was thrust into the spotlight and given a team of people to work with. Though many of Ryan's traveling campaign staff are those he has known for a long time and is comfortable with, he isn't used to having such a large team helping decide what he says.