Pundits, political commentators and bloggers skewered presidential hopeful Rick Santorum last month after he criticized liberal college professors for trying to indoctrinate their students.

Santorum's critics said he was out of step with the American mainstream and just flat wrong.

But a new survey of college presidents released last week shows Santorum's comments might not be unfounded after all.

According to the 2012 Inside Higher Ed Survey of College and University Presidents, 65 percent of college presidents say they plan to vote for President Barack Obama in the general election later this year, even though only 36 percent believe he fulfilled promises he made three years ago. Only 10 percent of college presidents surveyed said the Republican presidential candidates had articulated a vision that would help American higher education.

Approval of Obama was highest - 85 percent - among presidents of state schools that offer baccalaureate degrees.

Herbert London, a senior fellow with the Manhattan Institute, echoed Santorum's comments, attributing the overwhelming support for Obama to the "existing liberal bias" on college campuses. But supporting the president also becomes a practical decision, since almost all colleges get some funding from the federal government, London said. And given the general political leanings of a college president's constituents - students, faculty and alumni - it's not surprising where their allegiance lies: "If a university president wants to maintain good relations with alumni groups, faculty and the student body, they're going to swing to the left. It doesn't surprise me at all."

According to the survey, support for Democrats was much lower among presidents of for-profit colleges. Only 29 percent said they intended to vote for Obama in the fall. Forty-four percent of for-profit college leaders credited the Republicans with promoting a strategy beneficial for higher education. Both Santorum and rival Mitt Romney have voiced support on the campaign trail for colleges that operate as businesses.

The survey included responses from presidents at 1,022 colleges and universities, slightly less than a third of those who received it. More than one-third of respondents lead private institutions. The survey did not list the schools by name or indicate whether any responses came from Christian colleges, although it did exclude seminaries and other schools that focus exclusively on religious and clerical training.

London said both parents and students should be concerned about the nature of the university enterprise. People tend to assume that schools are open minded when they're not, he said. He also encouraged alumni, especially those who make regular donations, to question whether the alma mater's stance on issues is consistent with their own values. And if professors are attempting to proselytize students, parents should be aware of it, he said: "It is justifiable to ask, 'why should I send my children to an institution to be propagandized?' Professors are not there to preach, they're there to teach."