Forty percent of Americans now identify themselves as independents, the largest percentage in at least 60 years, according to Gallup.

Previously, the highest percentage of independents occurred in 1995 and 2007, when 39 percent of Americans identified themselves as not being aligned with any major political party.

"Increased independent identification is not uncommon in the year before a presidential election year, but the sluggish economy, record levels of distrust in government, and unfavorable views of both parties helped to create an environment that fostered political independence more than in any other pre-election year," Gallup explained.

The percent of Americans who identified as Republicans dropped from 29 to 27, while Democratic identification remained at 31 percent from 2010 to 2011. But Gallup found that independents tended to lean to the Republican Party rather than to the Democratic Party.

The results of the survey were gathered through 20,392 telephone interviews conducted in 20 separate Gallup polls in 2011.