I think it's more important to be willing to consider that being a Democrat or anything else can involve having a spectrum of different ideas. One of the charges I often get is that "Oh, you're a liberal" or "Oh, you're a conservative" the second one of my positions or arguments doesn't fit the neat and tidy doctrine of either ideology. As if anything other than lock-step agreement is a mortal sin and makes my ideas or contributions worthy of dismissal immediately.
It's more the willingness to be self-critical in the face of ideas that may present themselves different than your own formulation. You don't have to agree, of course, but it wouldn't hurt to consider that someone can agree with you for other reasons. Or someone might agree with you 90% of the time and that 10% is worth hearing out rather than declaring it enough to dismiss. Our blind loyalties are really more to our ideas, the parties just try to pawn themselves off as being in line with one or the other.