It gets silly. there's the whole "red state/blue state" thing which is a news media construct. Conservatives have traditionally had a financial fiscal policy of restraint. Some of those kind are still Repubs and not voting for Bush's Drunken Sailor spree.
Progessive seems to mean something else today then it did at the time of Henry Wallace's Independent Progressive Party.
One distinction that could be made is that Conservatives tend toward an authoritarian view of policies whereas Liberals tend to be well...more liberal.
Labels are used in marketing. These are tools to sell ideas whether political or widgits. "What is folk music" controversy is put in perspective when you consider that recording companies used the term "folk" to sell records to specific targeted customers. The same thing can be said about political labels. You can sell fear and loathing through labels and divide people and form alliances this way. Labels are a sort of enemy posing. It's kind of a Krips and Bloods wearing their colors.