Chicago ? While Barack Obama and his family were sunning on the beach in Hawaii last week, it was full speed ahead at his headquarters here. When I visited for the first time one day, the suite of rooms on the 11th floor of a rather posh office building on North Michigan Avenue – known as “The Magnificent Mile” – was filled with young people, most of them engrossed with the laptops on their desks.

I went there in part to take the temperature of Obama’s senior aides before next week’s opening of the Democratic National Convention in Denver. Having seen the Obama “machine” at work in places from Iowa to New Hampshire to South Carolina and elsewhere during the nomination fight, I was curious how they were gearing up for their first national campaign.

The answer to the first question is that they seem very confident. As for the second, they appear to have expanded the scope of their efforts without losing the purposeful focus that was so important in the defeat of Hillary Clinton and the other challengers.

I had just come from listening to George McGovern lament the lack of discipline that wrecked his 1972 nominating convention and, perhaps, his chance of challenging Richard Nixon. “My acceptance speech was the best speech I ever gave,” he said, “and it went on at 3 a.m. Eastern time, so nobody saw it.”

That is unlikely to happen to Obama. Now that he and Clinton have agreed – sensibly – on giving her the roll-call vote her ardent supporters demanded, no contentious issues of policy or procedure remain to be ironed out.

One of the people I interviewed, senior adviser Anita Dunn, said the convention goal is to present a “very future-oriented agenda, focused on solving key problems like health care. We’ll leave the negative messages to the Republicans.”

We’ll see. I will not be shocked if many of the Democratic speakers take shots at John McCain – but some of the partisan rhetoric may not make the one hour of prime time the networks have allocated to the Democrats each night.

The Obama people believe that McCain has squandered an opportunity to make a positive case for his own election in the many months since he secured the votes for the Republican nomination. David Plouffe, Obama’s campaign manager, argues that McCain is already feeling a backlash to his “negative attacks,” and the resulting skepticism may undercut any potential benefit he derives from the debates this fall.

But the Obama folks are not leaving it to chance. Plouffe said that “turnout is the big variable,” and the campaign is devoting an unusually large budget to register scads of new voters and bring them to the polls. “That’s how we win the Floridas and Ohios,” he said, mentioning two states that went narrowly for George W. Bush. “And that’s how we get competitive in the Indianas and Virginias,” two of six or seven states that long have been Republican – but are targets this year.

“That’s why I pay more attention to the registration figures than to the polls I see at this time of year,” Plouffe said. “The polls will change, but we know we need 200,000 new voters to be competitive in Georgia, and now is when we have to get them.”

That mindset – take care of business and don’t worry about irrelevancies – is what struck me in talking to Obama’s team in the primary states. Here, as in the states, they seem singularly devoid of turf battles or personal feuds.

Joe Rospars, who coordinates the computer files for organization, fundraising and communications, tested my limited knowledge of that world with a half-hour seminar on how these things work together. Rospars, who had a similar job in Howard Dean’s 2004 campaign, said “the big difference this year is not the technology, it’s the coordination.”

In all my hanging out, I got not a clue about Obama’s choice of a running mate. Patti Solis Doyle, the ousted Clinton campaign manager who will run the race of Obama’s No. 2, told me that – because she is flying blind – she had started an office pool. Her entry: Virginia Gov. Tim Kaine.

Two days later, Kaine’s predecessor, Mark Warner, was announced as keynoter, apparently a signal that Kaine will not be No. 2. It was a reminder that the Obama people may be organized but they still can be taken by surprise.