Obama and Romney are tied at 44 percent among registered voters in Iowa, with 10 percent of voters undecided in the state, MSNBC reported Thursday.
Obama has a one-point lead in Colorado, with support from 46 percent of registered voters against Romney's 45 percent. In Nevada, the president has 48 percent, while Romney is at 46 percent.
Obama won the three states in the 2008 election, though President George W. Bush won them in 2004.
"These are very, very competitive states," says Lee Miringoff, director of the Marist College Institute for Public Opinion. "Everything is close."
Registered voters in the three states have a more optimistic attitude about the economy, the poll showed, with the majority believing the worst is behind us, MSNBC reported.
A majority of voters in the states -- 54 percent in Iowa, 55 percent in Nevada and 56 percent in Colorado -- believe the nation is on the wrong track, the poll indicated.