September 24, 2013 4:21 AM EDT
If the Stormcloaks win the Civil War Ulfric and Elisif would both be contenders at the Moot since Ulfric does not kill her. However, I find it to be very unlikely that Elisif would be elected. And, under these conditions, with supporters of Ulfric installed as Jarls in each Hold, Ulfric seems unbeatable.
However, in the more interesting scenario in which Ulfric is defeated in the Civil War, I still find it somewhat unlikely that Elisif would be voted in by the Moot. She is young, and naive, and essentially lead around by the nose by her steward: Falk Firebeard. Her only claim is having been married to a High King, who was himself rather young and inexperienced. With all that said, I think it is possible that the remaining Jarls could conspire to vote for Balgruf, since I can't see him putting his own name forward.
In that situation, Balgruf would be honorbound to accept, and I think would make a great leader due to his allegiance to whatever is best for his people and Skyrim. He holds to Nordic tradition while also being a realist and seeing that times change and the Empire can be made to be useful to help defend Skyrim from the struggle within. Also, though he respected Ulfric, he saw the reality that what Ulfric and the Stormcloaks were trying to do would rip Skyrim in two and leave it easy pickings for the undesirable undercurrent in the Empire... the Thalmor.
All that said, I think that Brunwulf Free-Winter would make a decent High King as well.