Poly has no inherent political aspect other than that it is the opposite of patriarchy, which is a dominance based hierarchy, typically with the father as leader in the family - where in poly there is no inherent leader and may not even have one at all since personal responsibility and personal negotiation of relationship parameters is the norm.

I've written dozens stories about various aspects of how the dominance hierarchy aspects of the social system of patriarchy contrast with both current egalitarian impulses in the US and in other countries, as well as how it contrasts with our ancient ancestors -in the family and the larger society. Here's a link to that https://medium.com/inside-of-elle-beau/tagged/hierarchy. Scroll down to February of last year to find more of the anthropological ones.