I really hate it when people talk and act and think like generalized labels have a real meaning. Labels are not useless, but they are much less significant than most people would like. Yes, it's simpler to refer to large and diverse groups of people with one word. But 90% of the time, it's not meaningful.
For example, Peggy Noonan, in her 15 September article about the midterm elections, says, "I like Democrats. ... But I feel the Democrats this year are making a mistake. They think it will be a cakewalk." Ms. Noonan is a woman I have a deal of respect for, a political pundit but a thoughtful and generally wise one. But even she does not see the fallacy in assigning a single point on view or train of thought to a label that encompasses about half of the population of America. No doubt there are people who self-identify as Democrats who really do think that the Democratic Party will have an easy victory in November. From what I have seen and read in the news lately, there are also many who think the Democratic Party has a good chance at winning but who know that even with many factors in their favor, they will have to work as hard as they can- and even then nothing is certain.
I'm sure Ms. Noonan, who is no fool, is aware of this fact as well. It's simply easier, and better rhetoric, to pretend that 'Democrat' is a term that refers to a homogenous group. Unfortunately, talking this way says nothing meaningful about the issue.