To a point, both parties lean towards leaders who are more autocratic than democratic.  Think about how many Democrats were cheering Obama's use of Executive Orders to get stuff done, while I understand the reasons he went that route, I also understand that going that route does undermine our form of government at least to some degree.  That being said, the Rs do seem to prefer that type of leadership style while the Ds seem to end up there reluctantly.  The George W "You are either with us or against us" approach to governing is the approach many Rs seem to like.