Diff between social and political philosophy

At times when I wonder what the real difference is between these, I think of Wolin's distinction below. So how do you sort out the answer to the question of difference here between social and political (and politics for that matter, e.g. do political philosophers necessarily do social philosophy?) ? This is from "Fugitive Democracy" in Benhabib's book "Democracy and Difference":

I shall take the political to be an expression of the idea that a free society composed of diversities can nonetheless enjoy moments of commonality when, through public deliberationsk collective power is used to promote or protect the well-being of the collectivity. Politics refers to the legitimized and public contestation, primarily by organized and unequal social powers, over access to the resources available to the public authorities of the collectivity. Politics is continuous, ceaseless, and endless. In contrast, the political is episodic, rare. (31)