From The Volokh Conspiracy:
The Wall Street Journal notes a remarkable shift in an article today on page A4
(subscription required). In 2000, those with a high-school diploma or less
preferred Gore to Bush by 7 percentage points, and those who graduated college
preferred Bush to Gore by 5 percentage points. That is in keeping with what had
been a longstanding education gap -- college graduates have tended to vote for
the Republican candidate more (and for the Democratic candidate less), and the
reverse has been true for those who didn't complete college. (Those who went to
graduate school have tended to prefer Democratic candidates, but the Wall Street
Journal doesn't separate out those numbers in its story today.)
But in the polling for 2004, those with a high-school diploma or less prefer Bush 57%
to 38%, and those with a college degree prefer Kerry by 14 percentage points.
That's quite a shift (to put it mildly).
http://volokh.com/archives/archive_2004_10_21.shtml#1098905208