Obviously by "wins" I meant "becomes the (biggest party in a coalition) government", not "gains the most first preference votes" or some other strawman interpretation. And yes, I admit that it is hard to calculate the minimum number of extra votes that would need to be added to change which party leads the government, but I do think that a good proportional voting system should allow that number to be determined at least to a reasonable approximation.

> I'm not an electoral law expert, but complaints about election process go to National Electoral Committee, which can have its decision contested in Supreme Court.

I wonder how long that process would take in practice, and whether the Supreme Court would decide it had the power to invalidate an election. In particular, what sort of evidence would be required to satisfy the court that it had to demand that remedy? I imagine that "The opinion polls were wrong by 6%" might not be enough, and the political biases of the judges themselves might well be significant in such a situation.

> The e-voting over here is actual e-voting - the vote is purely digital and done remotely. Not in any way related to the digital vote counting machines used in the US.

Yes, the fact that the voting can be done remotely is another problem, since someone can be bribed or coerced into voting a certain way. I believe the mitigation for this is that the voter can supersede their online vote with an in-person vote, but an attacker could quite cheaply work around this by having tracking software on the victim's phone, and henchmen outside the polling stations.