For voters in all three states, the economy is the leading issue for the coming election.

Related list: Battleground states: The road to 270 electoral votes to win the presidency

A new NBC News/Marist poll released Thursday shows President Barack Obama and Mitt Romney in a virtual tie in the battleground states of Colorado, Iowa and Nevada.

In Colorado, a state Obama won by nine points in 2008, the new poll shows registered voters statewide leaning toward Obama at 46 percent, compared to Romney at 45 percent. Eight percent are still undecided.

Both men see matching numbers in favorability. The numbers show 47 percent of the Colorado electorate with a favorable impression of Obama, and 47 percent with an unfavorable view. Romney likewise has 43 percent with a favorable impression and 43 percent with an unfavorable opinion.

In Iowa, Romney and Obama are tied among registered voters at 44 percent, with 10 percent undecided.

"Both Obama and Romney are far from fifty percent in Iowa and have a lot of ground to cover," said Lee M. Miringoff, Director of The Marist College Institute for Public Opinion. "But Obama's supporters are less enthusiastic and less interested than Romney's, and this poses a special problem for the incumbent president."

In Nevada, Obama has a slight lead over Romney, edging him out 48 to 46 percent among registered voters. Five percent of voters are undecided. The numbers mean Obama is still within striking distance of carrying the state, Miringoff said.

Among Nevada's independents, Obama is ahead of Romney, 50 percent to 39 percent. Both men are tied at 47 percent among voters who have an excellent or good chance of voting. Among women, Obama is carrying the vote with 54 percent compared to Romney's 40 percent. However, among men, Romney leads at 52 percent to 41 percent.

Enthusiasm may become a major issue in the 2012 presidential election, and Romney carries the edge in this measurement. In Colorado, 52 percent of Romney supporters have a high level of enthusiasm about voting about voting, while only 43 percent of Obama supporters are similarly enthused. In Iowa, Romney carries the enthusiasm 51 percent to 43 percent. However, in Nevada, 50 percent are very enthusiastic about voting for Obama, compared to Romney's 46 percent.

For voters in all three states, the economy is the leading issue for the coming election. In Colorado, almost three out of four voters consider the economy to be most important, while 71 percent of Iowa voters say the economy is more important than social issues. Nearly eight in 10 voters in Nevada agree.