This evening, Barack Obama will deliver his acceptance speech for the Democratic nomination at Denver's Invesco Field to a roaring crowd of 75,000. Not since John F. Kennedy's nomination acceptance speech at the Los Angeles Coliseum in 1960 has a candidate stepped outside the convention venue to address the masses. It's daring, it's confident, but is it also risky? After all, it's a grand and wildly expensive stage upon which Obama hopes to portray himself as a man of the people, so you can expect to hear some grumbling.

I'm betting that you won't hear many complaints from his younger supporters, though. GenY is highly communal; they want to feel that they're part of something big and the more like-minded people they can gather around them, the happier they are. Take note: Obama's Facebook page now has over 1.4 million supporters (compared to McCain's 226,000); on the official campaign website, the largest single group is Students for Barack Obama. Let's face it the guy's a rock star.

But there's something else going on here as well. Obama's speech in Denver will resonate with young voters because the very grandeur of it will touch a cord of what Newsweek's Jon Alter calls "imaginative nostalgia" for the days of JFK and Martin Luther King. "This longing for an emotion they never experienced, but feel they missed, is part of what brings them out in such numbers at [Obama's] events," Alter wrote in a recent column. "Having come of age in the '70s, '80s or '90s, they see Obama not only as a ticket to the future, but a means of transporting them across the years to a mythic past, where politics could be a force for good." But Obama's challenge tonight will be to convince voters — young and old alike — that they're not just voting for the mythic past that his extraordinarily well-branded image invokes, but for a future that GenY's children might also look back upon with imaginative nostalgia. Will he succeed? Weigh in tomorrow.