The drop in those identifying as liberal was reflected in President Obama's declining share of the youth vote this election year. According to the Pew Research Center, he won 60 percent of the 30-and-under vote, a drop of 6 percentage points since 2008.

The results reflect growing acceptance of a number of issues that were once or are still considered by some socially taboo, including abortion and gay marriage. Support for abortion rights increased nearly 3 percentage points over the past four years among young Americans, bringing the level of support to 61 percent — and most of that increase, a 7-percentage-point jump, came in conservative students warming to the idea.

Nearly 80 percent of liberal students support abortion rights, up only slightly from 2008.

And as an increasing number of states nationwide begin to legalize same-sex marriage, so too are young Americans beginning to show increased acceptance of the practice. Conservative students saw a 4-percentage-point uptick in support for legalizing same-sex marriage from 2011, with 47 percent saying they support it in 2012. More than 90 percent of liberal students support legalizing it.

A full 75 percent of all students support the legalization of same-sex marriage, a steep rise since the question was first offered in the survey, in 1997. At the time, 51 percent of students supported it.

However, the belief in the need for a national healthcare system has eroded since 2008, from 70 percent then to 63 percent now. Liberal students have largely remained in support of the idea, but conservative students have dropped in support by 15 percent since 2008, down to 30 percent in support, and middle-of-the-road students have dropped in support by 7 percent, to 64 percent in support.

That reflects the continued shift in opinion against government healthcare across all ages. The most recent annual Gallup Health and Healthcare poll, conducted in November of 2012, was the first time since 2000 that a majority of Americans said they do not believe healthcare is the responsibility of the government.

The survey was conducted among 192,912 full-time first-year students at 283 colleges, and researchers weighted results to reflect an estimated 1.5 million students at 1,613 colleges across the country.