I have my own idea about the Dem's big philosophy (inspired by posts by Kos and Rena Phillips). Fundamentally, I think that what I call the "Three Commons" would have a huge impact:
1) Common Sense
2) Common Decency, and
3) The Common Good
Common Sense: sound judgement, straightforward arguments, rational problem solving, setting the right priorities, assigning competent managers and leaders, and in the words of Thomas Paine, "...in America the law is King. For as in absolute governments the King is law, so in free countries the law ought to be King; and there ought to be no other."
Common Decency: an insistance on treating all people with cordiality, respect, and dignity. Yes, criminals and terrorists should be caught and punished, but not through means that involve needless torture or the injury of the innocent.
The Common Good: looking beyond immediate self-interest to work towards something greater than oneself. As the saying goes: when everyone does better, everyone does better.