The New York Post has an article suggesting that Obama's opening to Cuba - restoring diplomatic relations and cancelling restrictions on the import of cigars and rum - may have irritated enough Cuban-Americans to swing Florida from Clinton to Trump. Absent FL's 29 electoral votes, Trump would not have gotten to 270, as he so far has 290.
Michigan and New Hampshire have not been called, one leans each way. We'd be sweating out their recounts, had not FL gone decisively for Trump. This was an unforced error, Obama could have waited until after the election to act.