I think ideology runs with the individual and thus those preconceived notions. I don't know if ideology is entirely by nurture or indoctrination but it appears to always run around 50% liberal vs conservative. My own theory is that it is genetic.
Driving wedges between the factions is the work of propagandists.
The votes simply don't exist at this time to make real progressive change possible. Give it a decade and you may see things swinging our way. Blame the propagandist, the parties, Our Corporate Overlords™, or whomever you will, without the votes things ain't a'gonna change.