Yes, under the succession act, the Speaker is next in line behind the President and VP. Therefore, the Speaker would be Acting President until we got a result. How long would that take?
However, the electoral votes are counted by the new Congress. The presidential term begins January 20 at noon (EST.) The new Congress begins its term January 3 at noon (EST.)
If we haven’t been able to sort this out by January 20, we may not have been able to determine who controls Congress by then either. (Boy, would that be a mess!)
After the Speaker comes the President Pro Tempore of the Senate. But if we don’t know who runs Congress, then we may not know who that is either. Next in line would be Secretary of State Pompeo.
This could keep hte popcorn industry in business.
You’ve really thought this through. If we have no leadership, that would be a good time for hostile countries to make some ominous moves.