Not well. The Feds have chosen not to enforce the laws in the states which have legalized marijuana. In fact a lot of marijuana laws have suffered from selective enforcement. Whether that continues with the incoming administration is a huge question.

I was listening to the Freakanomica podcast last week and it was discussing the power of the president and one commenter said that one of the presidents "real" powers is selecting which laws to enforce (via their Attorney General) there could be some huge battles coming up. Ironically if the Feds choose to enforce the federal laws in states which have legalized marijuana it would be contrary to the emphasis on states rights eschewed by most conservatives.