Im not sure, but I know in the case of a totally illegitimate election, you would essentially have no elected chain of command, since everyone elected would be illegitimate. In such a scenario the military takes over control and chain of command protocols are activated to ensure continuity of government. I think FEMA steps in and some other organizations, I dont remember all the details, but the military is in control under such a scenario.

At some point the military would then organize and run a new election using their own personnel and infrastructure to reinstate an elected government.