We also had that question during the presidential election regarding the language of the 20th amendment: "If, at the time fixed for the beginning of the term of the President, the President elect shall have died, the Vice President elect shall become President. If a President shall not have been chosen before the time fixed for the beginning of his term, or if the President elect shall have failed to qualify, then the Vice President elect shall act as President until a President shall have qualified..."
I'm guessing that it means certified by the controlling authority, in the case of Massachusetts meaning the Secretary of State certifying the election results.
-PJ