"One of my students asked me why it is that, in general, the more educated people are, the more they tend to be a little leftish?"

Well, one reason (among many -- I think it's a good and valuable question BTW) is because those who are in education/academia have remained there throughout their lives and therefore rarely, if ever, are faced with, or are involved with the pragmatic realities that often turn others to more practical economic considerations and realities that push one to more right-leaning ideas. For instance, a person in acedemia has a certain disconnect from concerns like productivity.

They are salaried and they don't have such income altering considerations as quotas. They get their pay on a more collective basis than most of the rest of the economy -- most have long since tied their earning power to the least capable in their discipline in order that all may achieve some sense of security.

Also, academia is a bit inscestuous in this regard. Time ran a recent article pointing out that, though they represent the extreme of the statistic, Ivy League schools have a professorship that votes 95% Democrat. Now, if the schools held in highest esteem in our country have that kind of imbalance, all the others who look to them for documentation on what they wish to refer to a "scholarship", they to are going to show the same leanings.

More educated people are more inclined to feel empathy -- that is, they are more able to put themselves into the feelings of others. (perhaps) sadly, this doesn't mean they are any more capable of discerning if that empathy is leading them toward solutions that may seem hard on their surface.

Just some guesses on my part.

(by the way, I am among a growing number that feels as though the older definitions of conservative and liberal are becoming useless -- must liberals I know (except for a very few holdouts) believe and understand market realties and understand that, in order to exist, most social programs will ultimately be very dependent upon the health of those market realities....
...and most conservatives I know (except for a very few holdouts) believe there are social programs that the government does do well.

It is usually the need for politicians to get elected -- and our failure to hold our own guys feet to the fire of truth that allows the extremes to define the middle -- for instance, those that hate Limbaugh, don't mind the same kind of inaccurate, emotionally volitile rhetoric from Michael Moore and vice versa.)