New Democracy, in power for four years, is due to win between 36 and 40% of the vote ahead of the left-wing Syriza party of former head of government Alexis Tsipras. The first partial results are due to be published in the next two hours but if ND's score is confirmed, it would not allow it to govern alone.
If it is impossible to form a coalition, a new election will have to be called. The winner of this second election would then benefit from a bonus of up to 50 seats that could give him a stable majority.