Here is an excellent article by the great Thomas Sowell on the differences in liberals and conservatives:

http://townhall.com/columnists/ThomasSowell/2008/09/09/the_vision_of_the_left?page=full&comments=true

Basically the right operates off of reason and logic gained from experience and the left operates off of emotions and feeling. This is the reason why the left so admires "feel good" legislation, such as hate crime laws, that doesn't actually accomplish anything.