Backstage at Barack Obama's Headquarters

Chicago, Illinois, Feb. 28, 2007— -- The Obama campaign had a handful of staffers 13 months ago — few enough to operate out of one conference room. Fast forward to the present, and Obama has 33,000 square feet of downtown Chicago office space and no one is exactly sure how many staff.

"We got big very quick," Obama campaign manager David Plouffe told ABC's Charles Gibson Thursday. "And from a budget perspective, that gave me some angst. But it was clear that there was so much energy out there."

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Plouffe says that Obama's was a little unusual for a presidential campaign because it had to build up operations in states quickly based on the huge numbers of people who wanted to volunteer.

"Barack's a community organizer, and what he did not want to have is people say, 'I want to help you,' and we'd say, 'Well, call us back in 10 months.' So we really had to build quickly to support that," he said.

Added David Axelrod, Obama's chief strategist: "We made some prudent decisions initially to grab space where we could."

The campaign got a great deal on the Chicago space, paying $12 per square foot. And it has raised most of that money in a new way — accruing large numbers of small Internet donations that amounted to a staggering $36 million in January alone.

"Our per-dollar donation is $109 and that is revolutionary," Axelrod said. "And it bodes well for the future."

Fundraising techniques are not the only new thing about the way this campaign is being run. The campaign watches its primary opponent, Hillary Clinton, on six monitors in real time. Clinton's camp is doing the same.

"Given the nature of news today, cable news and so on, when she's making a speech, we're generally watching that speech," Axelrod said. "It's a minute-to-minute pursuit and you need to be on your toes."

If Clinton says or does something and Obama's campaign hasn't responded within an hour, they consider it running behind.

The campaign never seems to rest. Plouffe confesses that apart from a week of vacation in August, which he says "was not really a vacation" except in the sense that he was absent from the campaign, he has taken only Christmas Day off. He called it "surreal."

"These days, with technology, you really don't get any time off. And this campaign, from the get-go, has been just at a ferocious intensity. Someone coined the term a marathon at a sprint pace, and that's how it's been since day one." he said.

Plouffe describes the campaign as a collaborative effort that distinguishes itself from other campaigns because it lacks the "headquarters versus the states mentality." The central mission of the headquarters, he says, is to support the states where most of the employees are.

The 20-somethings in the New Media department are responsible for everything from designing merchandise sold on the Web site to blogging to editing and uploading videos to managing chat rooms.

Axelrod says that the money flows through the computers — a steady infusion of cash in $10, $25 and $50 dollar. Computers also allow people to interact with the campaign.