Unique to the US, media is not allowed to cover the election until polls are closed. So there is little prognosticating that you find in the US. There is no predictions based on exit polls in the first few hours of voting. It is strangely quiet right now!
It is expected that the center-right party will win big. And the socialist-liberal coalition will lose big. The "game-change" is similar to what the US saw in its presidential elections last year. Of deep concern, a far-right party may come in second or third in total votes. As just one example of their extremism, this party is affiliated with a militia. Hungary is not alone with such extremist movements. You see them gaining popularity in Bulgaria, Romania, Holland and Britain. (To note, these movements are on the left and right).
It is an interesting time...
Hungary's electoral system is interesting and complex especially if you are used to the US electoral system. You can learn more here.