Exit polls suggest the radical left wing Syriza party has won elections in Greece by a wide margin, paving the way for the first eurozone government that is openly committed to cancelling its EU bailout programme.
Two polls issued after voting closed at 7pm local time (5pm GMT) by Greek state TV gave Syriza a victory of 12.5 percentage points, appearing to confirm the party's status as strong favourites going in to the election.
The polls suggested the incumbent Prime Minister Antonis Samaras's conservative New Democracy party would take second place with between 23 and 27 per cent of the vote, while the centrist Potami (River) party battled for third place with the extreme right-wing Golden Dawn, whose leaders are in prison pending their trial on accusations of running a criminal organisation.
It remained unclear whether Syriza leader Alexis Tsipras had done enough to secure the absolute majority required to govern alone - for that, they would need a minimum of 151 from an available 300 seats.
Tsipras has campaigned on a series of economic policies that could see Greece tear up the terms of its deal with creditors that has kept the country afloat since 2010.
"In Greece, democracy will return," the 40-year-old told a throng of reporters as he voted in Athens today. "The message is that our common future in Europe is not the future of austerity."
The exit poll on state-run Nerit TV projected Syriza as having won with between 146 and 158 seats. If it falls shy of the required 151 it will it will have to seek support from other parties — either in a minority government or as a coalition. But Greece's complicated election system meant that the proportion of votes won by smaller parties would have an impact on exactly how many it needs.
"It is a historic victory, we still have to see if it will be a big historic victory," Syriza spokesman Panos Skourletis told Greece's Mega TV.
Skourletis called the potential victory "a message against austerity and in favour of dignity and democracy" - but economists are concerned that Syriza's arrival in power would herald a huge challenge to the collective approach so far adopted by eurozone governments.
Financial markets have been on edge ahead of the elections, although confidence was boosted by the European Central Bank's massive quantitative easing programme announcement and an expectation that a Syriza-led government would seek a compromise.
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