"Whoever can grab the greater share of the attention of the Colorado independents is probably going to win the state's nine electoral votes," Schaller said, and then go on to win the presidency.
Moving west of Colorado to Nevada, registered Democrats outnumber Republicans by 50,000 -- the biggest gap in two decades.
Clark County is the fastest growing county in the United States, with 5,000 new residents moving there every month. It is home to the powerful Culinary Union, with 60,000 members who gave Obama their endorsement.
"We're very issues oriented," one culinary worker said. "We've been politically active for years. We've gotten people elected; we've gotten people taken out of office."
Then there's New Mexico. In 2000, Al Gore won the state by a little more than 300 votes. And, in 2004, President George W. Bush won by less than 1 percent.
"I grew up in New Mexico when people still asked, 'Do you have to get vaccines to go there?'" Teresa Brit-Asenap, a Canvasser, N.M., native, said. "For us to become a swing state in a presidential race, you're doggone excited about that."
New Mexico's rising Hispanic population has also changed the composition of the state's voters; with a Hispanic population of 44 percent, its state has the largest in the country.
Accordingly, Obama has focused on the Hispanic vote, saying that he will not take a single Hispanic vote for granted. His campaign has spent $21 million courting Hispanic voters this year.
"We've always been a swing state, but I think if you could do a swing state on steroids, that's what New Mexico is," state resident Brian Colon said. "We will determine who the next president of the United States is."