In the unlikely event that the alleged President-elect Joe Biden, 77, dies before the House of Representatives officially certifies the election on January 6th, the House of Representatives would elect the President. If Biden dies after that certification but before the Inauguration on January 20, then the Vice President-elect becomes the President.
If the House is required to elect a President in the event that Biden dies before January 6th, then each State delegation is afforded a single vote, with a total of 50 votes being cast. The Republicans have a majority in 27 State congressional delegations during the outgoing Congress, which will grow in the incoming Congress. Although the members of the House can elect anyone, the chamber would be expected to re-elect Donald Trump.
In that scenario, Trump would continue to serve as President — while Kamela Harris would be inaugurated as Vice President. Depending on the outcome of runoff elections for the two United States Senate seats from Georgia next month, an evenly divided Senate would make Harris the most powerful Vice President to ever hold the Office (given that she would serve as the de facto leader of the Democratic Party while being able to exercise the Office’s constitutional power to break tie votes while presiding over the chamber).
Meanwhile, Republicans are hoping that a lawsuit brought by the Attorney General of Texas, challenging the several swing States’ unequal application of their respective election laws between counties, will require the Supreme Court to overturn the outcome of the election. The Supreme Court has original jurisdiction in the case and is expected to hear oral arguments imminently.