No significant difference. Raging liberals prefer Wesleyan over Williams. In absolute terms, there are probably more “raging liberals” at Northwestern because it is a much larger school, just as there are probably more conservatives at Northwestern.
In my opinion, you are focusing on the wrong things. This is like trying to choose between a BMW sedan or a Jeep Wrangler based on the color of the upholstery. There are far larger and more consequential differences.