Sociologist Neil Gross, whose work on this subject I have cited before, disagrees with Rick Santorum’s claim and argues that “college doesn’t make you liberal“:

But contrary to conservative rhetoric, studies show that going to college does not make students substantially more liberal. The political scientist Mack Mariani and the higher education researcher Gordon Hewitt analyzed changes in student political attitudes between their freshman and senior years at 38 colleges and universities from 1999 to 2003. They found that on average, students shifted somewhat to the left — but that these changes were in line with shifts experienced by most Americans between the ages of 18 and 24 during the same period of time. In addition, they found that students were no more likely to move left at schools with more liberal faculties.

Similarly, the political scientists M. Kent Jennings and Laura Stoker analyzed data from a survey that tracked the political attitudes of about 1,000 high school students through their college years and into middle age. Their research found that the tendency of college graduates to be more liberal reflects to a large extent the fact that more liberal students are more likely to go to college in the first place.

Studies also show that attending college does not make you less religious. The sociologists Jeremy Uecker, Mark Regnerus and Margaret Vaaler examined data from the National Longitudinal Study of Adolescent Health and found that Americans who pursued bachelor’s degrees were more likely to retain their faith than those who did not, perhaps because life at the bottom of the socioeconomic ladder can be rough in ways that chip away at religious belief and participation. They report that students “who did not attend college and two-year college students are much more likely — 61 and 54 percent more, respectively — than four-year college students to relinquish their religious affiliations.”…

The main reason for this development is that attacking liberal professors as elitists serves a vital purpose. It helps position the conservative movement as a populist enterprise by identifying a predatory elite to which conservatism stands opposed — an otherwise difficult task for a movement strongly backed by holders of economic power.

Is this enough research to satisfy critics or do the studies not really matter in the face of political concerns?

While these studies might show that students are not all being pushed into liberalism, I imagine conservatives might bring up other arguments. For example, professors have a certain level of prestige in society and so if a majority are proponents of liberal opinions, then society could be swayed in certain directions. Policy decisions might be made. Public opinion could be influenced (though this might require suggesting that Americans are easily swayed). Or another issue: colleges and universities receive federal funding and so liberal professors can access taxpayer money to promote their causes.

Academics tend to brush aside these arguments by suggesting they can still be objective researchers (and I tend to agree) regardless of their own political or personal opinions. But there is still a perception issue here that academics could work harder to dispel. At times, I think it wouldn’t take much: show some respect for religion, stop suggesting that people with traditional or conservative ideas are all ill-intentioned, hint that popular culture and the suburbs aren’t a complete wasteland, and don’t be condescending.