If the Electoral College elects a future President and that person dies before taking office, would the Vice-President elect become President?
Government FAQ on the Electoral College:
If a winning Presidential candidate dies or becomes incapacitated between the counting of electoral votes in Congress and the inauguration, the Vice President elect will become President, according to Section 3 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. [...]