Obama and Romney are tied at 44 percent each in Iowa, including respondents who are leaning toward a candidate, with 10 percent undecided. Obama won the Iowa caucuses in 2008, becoming the first African-American candidate to win the contest of overwhelmingly white voters, and went on to win the state in the general election.
In Colorado, Obama has an indistinguishable 46-45 edge over Romney, including those leaning toward a candidate, with 8 percent undecided. Obama won Colorado by nearly nine points in 2008, after George W. Bush carried the state in 2004.
In Nevada, Obama has a 48-46 edge, including leaners. 5 percent are undecided. Obama won the state in 2008 after Bush carried it in 2004.
Voters expressed conflicting feelings about the future -- majorities in three states said the worst is behind us, but also said that the country is on the "wrong track."
The polls measured registered voters and have a margin of error of +/- 3.0 percent.
Polls released by NBC/Marist on May 24 showed Obama with an edge over Romney in Florida, Virginia and Ohio.