A new round of NBC News-Marist polls shows President Barack Obama and Republican Mitt Romney running almost neck-and-neck in three key battleground states, with Obama holding a slight advantage in Michigan and North Carolina, and the two candidates tied in New Hampshire.

Click here to read the NBC News/Marist Poll of New Hampshire

In Michigan, Obama is ahead by four percentage points among registered voters, including those who are undecided but are still leaning toward a candidate, 47 to 43 percent.

Click here to read the NBC News/Marist Poll of Michigan

In North Carolina, the president gets 46 percent to Romney's 44 percent, which is within the survey's margin of error.
And in New Hampshire, the two men are tied at 45 percent each.

Click here to read the NBC News/Marist Poll of North Carolina

"Everything is very close," says Lee Miringoff, the director of Marist College's Institute for Public Opinion, which conducted these surveys.

In 2008, Obama won Michigan and New Hampshire – which had been competitive states in previous presidential elections – by double-digit margins. And he carried North Carolina, a reliably Republican state since 1980, by just 14,000 votes.

In all three states, Obama's approval rating remains above water -- or right on the surface. In Michigan, 48 percent of registered voters approve of his job, while 42 percent disapprove.

In New Hampshire, it's 47 to 45 percent, and in North Carolina it's 47 to 47 percent.

Romney calls Obamacare 'moral failure'

As for Romney, his favorability rating is upside down in two of the three states. In Michigan, 37 percent say they have favorable impression of the former Massachusetts governor, and 43 percent have an unfavorable opinion. In North Carolina, Romney's fav/unfav is 40-42 percent.

The lone exception is in New Hampshire – which borders Massachusetts, and where Romney owns a home – it's even at 45-45 percent.

Mixed results on the economy
The issue of the economy is a mixed bag in each of these three states, as well.

Majorities say the country is headed in the wrong direction, but nearly equal majorities believe that Obama inherited the current economic conditions.

In Michigan, the president holds a narrow edge over Romney, 44 to 42 percent, when it comes to which candidate would do a better job handling the economy.

Romney, meanwhile, leads on this question in New Hampshire, 46 to 42 percent. And they are tied in North Carolina, at 43 percent.

"The economy plays both ways in all three states," Miringoff says.

Obama leads big with Hispanics, but they're not fired up and ready to go yet

In New Hampshire, adding Sen. Kelly Ayotte (R-N.H.) to the GOP presidential ticket doesn't improve Romney's standing in the Granite State.

A Romney-Ayotte team won the support of 43 percent of registered voters, versus 45 percent for Obama and Vice President Joe Biden.

In a hypothetical contest for Michigan's Senate seat, incumbent Democratic Sen. Debbie Stabenow leads former Republican Rep. Pete Hoekstra by 12 points among registered voters, 49 to 37 percent.

NYT: Future of aging court raises stakes of 2012 vote

And in North Carolina's gubernatorial contest, former Charlotte Mayor Pat McCrory, the Republican nominee, gets 43 percent, while Democratic Lt. Gov. Walter Dalton gets 41 percent.

These three NBC-Marist surveys were conducted June 24-25 by landline and cell phone of 1,078 registered voters in Michigan, 1,029 registered voters in New Hampshire and 1,019 registered voters in North Carolina.

The margin of error for the New Hampshire and North Carolina poll is plus-minus 3.1 percentage points, and it's 3.0 percentage points in Michigan.