The rules:
1) All demigods are sufficiently sane as to make their best effort in campaigning, but if their body has changed in-game those changes remain.
2) Every being in the Lands Between and the Land of Shadows gets a vote so long as they can speak or write. If they don't know how to write but could theoretically learn, they will learn in time for election day
3) The voting system is as follows: every voter will give each candidate a score correspondimg to descending order of preference. This means that, if there are three candidates, a voter will give a score of 3 to their favourite, of 1 to their least favourite, and of 2 to the middle. The candidate which accrues the highest score will ascend to the Elden Throne.
4) Interfering with the ballot is physically impossible: no power in the universe or beyond will enable anyone to tamper with the votes, spy on the voters to know how they cast their ballot, or prevent anyone from exercising their right to vote how they see fit.
4a)This includes Miquella's Charm: even while the victim is still controlled, they will be inescapably compelled to express their true preferences on the ballot. He is aware if this.
5) Messmer gets to participate.
6) Voters will, at the start of the campaign, only know what they would normally know about each Demigod, but candidates can dig up dirt on their rivals and attempt to counter such moves against themselves
7) Candidates cannot be killed, banished, or otherwise prevented from running until the election is complete.
8) Each Demigod starts with whatever followers and servants they have in game as their campaign staff and promoters. They can acquire more or lose some depending on what happens during the campaign.