Exactly what kind of timescale are you talking about? Would coalitions and the time needed to form them not be an option in your model?
There would be no time to throw more resources at it. Like trying to prepare between rounds in boxing, compared to preparing between fights.
So you would expect a second ballot to be run in exactly the same way as the first? There would be no attempt to change tack and sway voters? If anything, it could cost more as parties would (want to) throw more resources at it to get them over the line