Athens - Greeks angered by austerity took to the polls on Sunday for an election that could decide their future in the eurozone amid unprecedented external pressure not to vote for a radical leftist party.
Some 9.8 million Greeks began voting at 04:00 GMT in what is expected to be a close contest between the pro-bailout New Democracy conservative party and the anti-austerity Syriza party that has spooked European leaders and the markets.
Greek newspapers said the vote was the most critical since the end of military rule in 1974 as conservative chief Antonis Samaras argued that a "new era" would begin for the recession-hit eurozone state on Monday.
"Today the Greek people speak. Tomorrow a new era starts for Greece," Samaras told reporters in his hometown of Pylos in the southern Peloponnese peninsula.
To Vima weekly spoke of a "salvation ballot" with Greeks voting under a "visible danger" of exiting the euro.
"A vote on the euro, Greece in its most critical electoral confrontation," said the Ethnos daily.
"This moment is very critical. This is an election that makes people very, very anxious," said 62-year-old pensioner Andreas Pappas after casting his ballot at a polling station in an elementary school in central Athens.
"I want Greece to remain in the eurozone and the European Union. We used to think it was something we could take for granted," he said.
German Chancellor Angela Merkel on Saturday said it was "extremely important" for Greeks to elect lawmakers who would respect the terms of a controversial bailout, which Syriza leader Alexis Tsipras says will be "history" on Monday.
Eurogroup chief Jean-Claude Juncker also warned on the eve of the vote that choosing Syriza could have "unpredictable" consequences for the eurozone as international markets watched the momentous vote with bated breath.
Many Greeks would grudgingly admit Juncker has a point.
"We signed something (the bailout deal). We can't just take it back," said 68-year-old Emmanuel Kamkoutis after voting for a centre-right party.
"I want a pro-European government and not a communist one," he said.
Voting ends at 16:00 GMT, with exit polls also due out then and the first indicative results expected at around 19:00 GMT in the second election in six weeks after a vote on May 6 failed to produce a government.
Germany's Bild newspaper added to tensions ahead of the vote with an open letter telling Greeks their ATMs only had euros because "we put them there."
"If the parties who want to be through with austerity and reforms win the election and contravene every agreement, we will stop paying," it said.
Tsipras argues that the mood in Europe is shifting against austerity and that the European Union and International Monetary Fund will not want to risk a Greek euro exit that would send shockwaves through the global economy.
At his final campaign rally, he accused New Democracy leader Antonis Samaras of defending "Merkel's Europe of the past".
"We guarantee the Europe of the future," he said.
Samaras wants a more moderate renegotiation of the bailout deal and warns that a vote for Tsipras could bring back the drachma currency.
Polls show an overwhelming majority of Greeks want to keep the euro.
"We will exit the crisis. We will not exit the euro. We will not let anyone take us out of Europe," Samaras said at his last election meeting.
In their public comments at least, European leaders warn that Greece must respect its international debt commitments or risk leaving the euro club, and the EU and the IMF have suspended loan payments until after the elections.
Greece has already been forced to seek bailouts twice, first for €110bn in 2010 and then for €130bn this year plus a €107bn private debt write-off - for a total of €347bn.
There have been suggestions that there is at least some room for compromise on the bailout conditions and a former Greek government adviser said a crucial deficit-cutting deadline could be extended to 2016 instead of 2014.
But for many Greeks a fine-tuning of the terms of the loans may not be enough as public anger is rising against the steep pay and pension cuts seen since the crisis first exploded in 2009, setting off a chain reaction across Europe.
Greece is now in its fifth year of recession, and many young Greeks are voting with their feet by emigrating, while local media reports warn the state will run out of cash to pay public-sector salaries and pensions on July 20.
No single party is expected to win enough votes to secure a majority in parliament, and the days to come are likely to be dominated by coalition talks.
Analysts say New Democracy would find it easier to form a coalition if it wins - although it might struggle to secure a strong majority in parliament.
It may be trickier for Syriza to set up a leftist coalition.
"But both scenarios are not very easy," said Vassiliki Georgiadou, a political science lecturer at Panteion University in Athens.