I've been to a lot of presidential campaign rallies over the past two years. The best, without a doubt, occurred on a frigid night back in January, when Barack Obama won the Iowa caucuses. His victory rally was in Des Moines, at a place called Hy-vee Hall, and the event—no surprise—was loud, joyous, and shot through with a deep sense of history. "Years from now," Obama told the audience, "you'll be able to look back with pride and say this was the moment when it all began... this was the moment, this was the place, when America began to hope again."

There were other exciting rallies, and many that were less exciting than they were revealing. Take, for example, one held by Hillary Clinton in Southern Oregon in early May, long after it was clear she would lose the nomination. Her advance staff had to take seats away, so as not to let the press see empty chairs, and the supporters lining up to get inside were overwhelmingly white and often very misinformed. Philip Frisby, an 84-year-old former cement truck driver from Grants Pass, told me then that Obama believes the national anthem is a war song. "His patriotism goes one way," Frisby said. "His way."

There were other telling rallies. In June of 2007, Dennis Kucinich supporters gathered in New Hampshire in the back room of a restaurant that, if it wasn't a T.G.I. Friday's, was a close approximation. The candidate stood near a table of vegan finger-food and promised victory. There was Ron Paul, in July of 2007, telling a large crowd near the Google headquarters in California about the perils of empire (while on the periphery, some of his more paranoid followers warned about the impending union of the U.S. and Mexico). And there were rallies in Washington State: Obama at KeyArena on the eve of our February caucuses, Clinton in a muggy hangar at the Port of Seattle during the same period, John Edwards at a Boeing union hall.

There's an art to pulling off a good campaign rally, and it is the Obama campaign that most effectively mastered it this cycle. Their skill was on vivid display on October 19 in Tacoma, at what was probably my last big political rally of this campaign season. The setting: a small outdoor baseball stadium in a working-class section of a working-class city. The speaker: Joe Biden. The positioning of the stage in the late-afternoon light: perfect.

Biden gave a strong speech, in front of what was reportedly the largest crowd he's had this fall, but more important may have been what the Obama campaign bluntly communicated before word one. Stevie Wonder's "Signed, Sealed, Delivered, I'm Yours" played over the ballpark loudspeakers. A giant American flag hung from the top of the right-field stands. And in every camera sight-line, there were placards and banners bearing the simple, winning message that the campaign has hammered home ever since Obama's historic win in Iowa: Change.