The struggle of progressives will always be just that... a struggle. It will be a struggle because it's premised on truth and facts. The tendency of all cognition is to ignore those truths and facts that aren't appealing to our desires and wishes. It will be a struggle because the tendency of the left is to advocate justice, yet justice entails fairness and reason and it's difficult to explain to those with power over others why one ought to pursue these virtues. It is for this reason that Republicans represent the party of human nature... and by that I mean what is most primative and base in our nature. It's the duty and responsibility of Democrats to represent humanity as it ought to be or could be.