What citation style is mainly used in political science? According to Wikipedia, the most pertinent styles are Chicago and APSA, which is a variant of Chicago. But I could not find stronger references about this.

EDIT. The purpose of my question is the following. I am trying to build a quick help-sheet for scholars and students about the "citation" topic. Political science seems to be a discipline not very careful about the citation styles issue (compared to the STM fields), so I can't find clear information about the practice of its community.
Political Scientist here. @aeismail is correct - different journals use different citation styles, as do different academic publishers. The best way around this is to use a reference manager (such as Mendeley or Papers) to not only manage your academic articles, but cite directly into your publications. These software packages are capable of formatting your citations in whichever style necessary.

With that said, my experience is that, generally, APSR's citation style is broadly accepted, with minor variation.