Implausibly, Barack Obama is president. How could that be? Some Washington pundits insist that if Clinton were savvier, McCain younger, or the economy less melted, it wouldn’t have happened. But I disagree. Obama is optimistic, charismatic, and unpoisoned by 40 years of bad political mojo. And he had one more crucial thing going for him: He realized early on that he couldn’t win unless he completely changed the American game of politics.

That’s where you entered the picture. The thesis of “Blame Us,” our sprawling and entertaining story, is that without radical Bay Area innovations, Obama would be back in the Senate, and politics would still be the infuriating costume drama it’s always been. We taped interviews with scores of participants in Obama’s journey, from his earliest adopters to online pioneers to regular people who found themselves walking the virtual streets to support their candidate. Their oral his­tory vividly brings back all the excitement of Obama’s rise.

It also renders a pointed argument: If the Bay Area hadn’t fueled the explosion of the Internet; if eBay and PayPal hadn’t proved that people will gladly send money online; if the founders of rebel websites MoveOn and Daily Kos hadn’t given the Democrats some cojones; if Silicon Valley VCs hadn’t turned their startup model loose on grassroots politics; if Facebook hadn’t newly unleashed the power of peer-to-peer persuasion; if we were all still watching the candidates on the idiot box, rather than in YouTube clips sent by friends—politics would still be the same tired, rotten, unviral enterprise, even if we had elected the first woman president.

We know it’s a bold claim that without all these Bay Area–based online milestones, Obama could not have won the White House. But take a moment to imagine the presidential race absent of the Bay Area resources Obama embraced as his own—or absent of the Bay Area at all.In this backward universe, no one sees the future before anyone else—no Google. There’s no sense of the Internet as a global common space where neighbors stop in to swap information, argue, and make plans—no Craigslist—and no sense of the Internet as a fast-paced playground for the young—no Twitter. There’s nobody who thinks their job is to spot great talent, fund long shots, and scale winners—no Kleiner Perkins. The Internet, if it even exists, came out of Mumbai, not Menlo Park. Silicon Valley is called the Peninsula. And that means there’s no route for Obama to beat Clinton—no means to raise $750 million, to link volunteers in a flaw­lessly organized, on-the-ground effort, to unleash us all to vigorously argue Obama’s case inside the messy new-media ecosystem. So there’s no way for him to make his campaign, as Rolling Stone contributor Tim Dickinson told me, “as off the charts as Yahoo! or Google. I don’t know the term for that phenomenon—maybe Google-ian.”

As you’ll discover, Obama realized from the start that after Chicago, the Bay Area was his base. Whereas Clinton found Susie Tompkins Buell and friends here, and McCain mostly found flak, Obama sought and received everything that he needed to launch himself to victory. Besides, of course, what he already had: his geeky self.