(CBS News) WASHINGTON - Early voting began Saturday in both Maryland and Florida, the battleground state that was at the heart of the disputed 2000 election. And in Colorado, voting has been underway since Monday. The most recent poll there shows the candidates in a dead heat, which is why both sides are going all out.
In Boulder County, Colorado, Matt Romney joined volunteers going door-to-door.
"Hi there. I'm Matt Romney," he said, "Mitt Romney's son. He's running for president."
The campaigns are getting down to basics, hoping personal outreach will help push those final votes.
More than 70 percent of Colorado voters are expected to vote before Election Day. With the candidates tied, both parties are scrambling to get as many ballots as possible in the bag.
At the University of Denver, Steph Winsor and the young Democrats were canvassing the campus, offering coffee and doughnuts to help energize the base.
Nationally president Obama still dominates the youth vote. But a Harvard Institute of Politics study finds more young Romney supporters say they will definitely go vote.
"If everyone voted who wanted to vote -- who could vote," said Winsor, "we'd be blue without a doubt. The issue is getting them to the polls."
First-time voter Stephen Stanis says he's definitely going to vote -- he's just not sure for whom.
"It's just a matter of trying to figure out where I stand in the political landscape," he said.
And the pressure to choose is building, he says, fueled by strong supporters on both sides of the race.