The term "moderate" is used by predominantly anti-gun, anti-self defense party representatives to describe opposition party representatives who might be be manipulated. The term "moderate" is seldom used to describe representatives of the predominantly anti-gun party.
It isn't used to describe the antis because those are mostly people from the outer edges of one ideology. Those at both the edges use "moderate" as a pejorative.
However, moderates make up the majority of the voting public, and analysts and pollsters are wise to take their opinions into account. Those are the people 2A activists have to sway, and to look at it lately, we're not doing so good of a job.