The setting, on a sparkling day in this battleground state, said perhaps more than Obama did in his actual speech. It rippled with the kind of enthusiasm found at victory rallies.
The location of a later rally - a Colorado State University lawn known as "The Oval" - suggested Obama's possible future workplace. He spoke to an estimated 45,000 people at the Fort Collins event.
Obama's campaign is capitalizing on the scope of such rallies to get people to cast votes early, which is permitted in Colorado and more than two dozen other states.
"How many people have early-voted?" Obama said, eliciting cheers from people bundled up in fleece. "That's what I'm talking about. No point in waiting in lines if you don't have to. You know who you're going to vote for."
Still, wary of complacency or overconfidence, Obama keeps warning supporters that they must fight during the rest of the campaign. His opponent, Republican John McCain, is needling Obama for starting his victory lap without having won anything.
Polls put Obama ahead in Colorado with the number of campaign days remaining now down to single digits.
It was in Denver that Obama, in his groundbreaking campaign, accepted the Democratic Party's presidential nomination at the stadium where the Denver Broncos play.
"Do you ever have small crowds in Denver?" a smiling Obama said. Members of the crowd interrupted Obama's standard campaign speech with shouts of "Obama!" and "Yes we can!"
Traditionally, Colorado has gone for Republicans in presidential races, including twice for George W. Bush. Obama is trying to snag a win here as part of a multiroute path to capture at least the minimum 270 electoral votes on Nov. 4. Colorado offers nine electoral votes.
In Fort Collins, Obama seemed to revel in what was unfolding. "What a spectacular crowd and a spectacular day," he said.
Obama also jumped on McCain's comment, made during an interview on NBC's "Meet the Press," that he and President Bush share a "common philosophy" of the Republican Party.
"I guess that was John McCain finally giving us a little straight talk, owning up to the fact that he and George Bush actually have a whole lot in common," Obama said in Denver.
