Carolyn Kaster, AP
FILE - In this April 25, 2012 file photo, President Barack Obama arrives to speak at the University of Iowa in Iowa City, Iowa. The Iowa magic that launched Barack Obama to the presidency four years ago has all but faded. Today, the Democrat who emerged Cinderella-like in Iowa in 2008 is sharply attacking Republican challenger Mitt Romney’s economic credentials and his ability to grasp voters’ everyday concerns. (AP Photo/Carolyn Kaster, File)

President Barack Obama holds a slim lead over probable Republican nominee Mitt Romney in "three of the most pivotal presidential battleground states — Florida, Ohio and Virginia," according to recent NBC-Marist poll information released in an MSNBC article.

Obama's lead is certainly not insurmountable, as he holds a four-point margin in Florida and Virginia, and a six-point lead in Ohio, according to the article.

"In each of these states, Obama's share of the vote is below the 50 percent threshold usually considered safe haven for an incumbent president, and Romney has narrowed the margin in these three battlegrounds since earlier this year," writes senior political editor Mark Murray in the article.

Murray also provides insight about a major factor that is influencing voters in these states. He writes, "Benefiting Obama in these three states is a sense that the economy has improved. Majorities in all three battlegrounds believe that the worst is behind us, rather than the worst is yet to come. That said, 40 percent or less think that the economy will get better in the next year."

In a recent New York Times article, author Nate Silver provides additional information on how and why the voters in certain states can influence an election more than others. Silver introduces a new concept, elastic states, to help clarify confusion on the issue.

"Let’s define an elastic state as one that is relatively sensitive or responsive to changes in political conditions, such as a change in the national economic mood," Silver writes in the article. "(This is in the same way that, in economics, an elastic good is one for which demand is highly sensitive to changes in prices.) An inelastic state, by contrast, is one which is relatively insensitive to these changes. In an inelastic state, a 5-percentage-point change in the national environment might only affect Mr. Obama’s numbers by 3 percentage points instead."

Silver's article provides charts and statistics for various states to define their "elasticity" and their potential influence in the upcoming election.

"States like Ohio and Florida, finally, are swing states that have about average elasticity," Silver writes. "In these cases, the Democratic base, the Republican base and the number of swing voters are all close to the national average."