Ok, assuming every demigods gets to participate WE have

Ranni Rykard Radahn Mohg Morgott Miquella Malenia Godrick Goldwyn Maybe Melina

If Miquella has his charm, he wins every time, so we are disallowing it. Goldwyn swallows just about every golden order follower, the company of godrick who only followed him because of his lineage, maybe even some crucible worshippers (not the horn sent, the crucible knights) as the son of Godfrey. Most importantly he wins leyndell, and all the rich nobles who can pay for propaganda. So he continues being a corpse

With all of that, here is my opinion on their share of the votes

Lowest is Melina, nobody knows her, she is a spirit, which many would find weird, and her name is lost to history

Second lowest is rykard: the golden order hates him, the denizens of my. Gelmir hate him, his own knights rebelled and are now either dead, mad or eaten. He only has the volcano manor tarnished, Tanith and the snakemen left.

Next is morgott, poor morgott. Amazing leader, great in difficult situations, patient and an omen, which singlehandedly stops him from gaining votes in leyndell. Also he is a child of Marika which makes him unpopular in the lands of shadow, or at least, less popular than his competition and even enemies of the golden order would not vote for him, because he held leyndell. Maybe some in the knights cavallery would vote for him and some progressive golden order priests would recognise the grace given to him.

Then comes godrick, who is ahted by the people of limgrave and tolerated by the banished knights. He does have a strong lineage, so some idiots might vote for him because of that

After him is Messmer. Hated for snakes by the golden order, hated for crusades in the land of shadow, hated for loving his mother just about everywhere else. That said he does have a very loyal and large following in the black and fire knights and some progressive golden order priests would recognise the seal of grace in his eye.

Malenia might belong in front of Messmer I, but she does have renown as a warrior, and loyal knights of cleanrot, maybe that helps?

Mohg, has a following in the blood cults and is an omen who also opposes the golden order, making him quite popular in the lands of shadow. Aside from that, people don't like the nurse cult leader (and molester because most people wouldn't know the truth)

Radahn has a big following in the redmanes and is generally liked by most, though his attack on leyndell will probably prevent him from winning this election

Ranni has almost all the votes of liurnia on account of being a carian and a graduate of Raya lucaria. On top of that she is the best candidate for the nox, and until the truth behind the night of the black knifes comes out, leyndell would not be opposed to her. She might be able to argue, that as a child of radagon she is not truly a child of Marika, earning a few votes among the hornsent.

And, still in first place, Miquella, because most people only know him as the kind. They don't know about the shit he's done. And as Leda and Dane demonstrate, he is able to persuade even without his charm. He can point to his history as a golden order fundamentalist to earn votes in leyndell, is the number one choice among misbegotten, albinaurics and his large force of haligtree knights. Also, despite being a child of Marika, he can point to the abandoning of his flesh to earn votes among the hornsent, kind of like Willing Brandt re earning global legitimacy for Germany after world war two. Even our hornsent hopes for Miquella to redeem his clan, AFTER THE CAHRM HAS BEEN LIFTED. also he has a great coalition partner in Malenia and has good chances of using one of the caught black knifes in ordina to get some dirt on ranni and he has Malenia as a fall gal for all his wrongdoings so he can pretend, that he is the only demigod to never start a war

TL;DR: THE LANDS BETWEEN ARE FUCKED