My husband is growing on José Luis Espert (more info here). He is an economist and is running as an independent candidate. I think that politics is, nowadays, a strongly bipolar system. My husband is explaining me that the first round of election has no consequence on the final results. We will vote twice (or thrice in case of ballot) anyway.
I don't see the point in having to vote twice just to 'test the ground'. Making an election is very expensive, making a fake one is pointless.
Maybe Carlos can explain the reason of two votes.