...because college doesn't make you more liberal:
It’s also true that young college graduates are somewhat more likely to identify as liberal and to hold more liberal attitudes on social issues than their non-college-educated peers.
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.
The article fails to mention the fact that reality has a known liberal bias, which may also be a factor.
Since I don't wish to make every blog post about Santorum this week, also check out this New York Times article about Santorum's religious evolution -- it's a fascinating read, regardless of whete you stand on all things Rick.