I'm not sure it's easy to separate the two categories cleanly, not least because some organizations deliberately exploit favourable drifts in the political climate, and other organizations actively alter the political climate to further their goals.

Setting that aside, I can't immediately think of good rules of thumb to answer your question; I'd probably try answering it on an ad hoc, case by case basis. Looking for repeated successes sounds like a sensible general heuristic, though.