This page in a nutshell: This page summarizes the relationship between the GNG and the various SNGs that can be used to establish the notability of a topic.
There are multiple relations an SNG can have to the General Notability Guideline (GNG):
exclusionary override - Some references are excluded from consideration in evaluating notability.
inclusionary override - Some statistical/directory reference are included in consideration in evaluating notability.
independent - Some pages are not easily evaluated by the GNG, and topic suitability is generally assessed by the SNG.
advisory - Pages must meet the GNG, but pages that meet the SNG are often given the benefit of the doubt in deletion discussions.
Athletes that meet SNGs (particularly the ones involving participation in named sports leagues or the Olympics) are generally kept even if non-statistical references cannot be found.
People who have served in various high-level political positions are included even if GNG is not clearly met. People who are merely candidates for political office are generally excluded if their only coverage is in the context of a campaign.
There are no clear guidelines on when "news events" are notable; the common misconception that contemporaneous newspaper articles are "secondary references" makes this even harder.