Their efforts appear to be bearing fruit. Democrats have an edge in votes cast in Florida, Iowa, Nevada, North Carolina and Ohio. Republicans have an advantage in Colorado.
Obama's campaign says boosting early vote totals could put some states out of reach for Romney even before Election Day. In Ohio, for example, Obama aides estimate the Republican would need to carry at least 53 percent of the vote cast there on Tuesday in order to remain in contention.
It's more than just party registration that has Obama's team feeling confident. They tout data showing two-thirds of those who have already voted were women, young people, blacks and Hispanics. Obama is almost certain to win the majority of those voting blocs.
Aides say minority voting in particular is on track to reach an all-time high, perhaps as high as 28 percent of all voters.
Follow Julie Pace at http://twitter.com/jpaceDC
Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.