Greek Prime Minister, the left-leaning Alexis Tsipras faces possible loss in the elections as voters favor center-right Kyriakos Mitsotakis.
Greeks voted Sunday in the first general election since the country emerged from international bailouts, with polls predicting that conservatives were set to return to power and end four years of center-left rule under Prime Minister Alexis Tsipras.
The polling stations opened at 7 am local time and will close 12 hours later when the initial exit polls will begin to roll out. According to official figures, 9,903,864 people, including nearly 520,000 first-time voters are registered to cast ballots.
Tsipras called for the vote three months before the end of his term after his party Syriza suffered a 9.5 percent defeat during European Parliament elections in May.
According to opinion polls, the center-right New Democracy party, led by Kyriakos Mitsotakis leads with around 10 percentage points ahead of ruling Syriza, potentially giving it an absolute majority in Greece's 300-seat parliament.
"This is a critical battle," said Prime Minister Alexis Tsipras who stormed to power in 2015 vowing to tear up the austerity rule book only to be pressured by neoliberal European governments and the International Monetary Fund (IMF) to do the opposite.
"We are fighting it with optimism and determination ... so that the sacrifices and hard work of our people do not go to waste," he said after casting his vote in Athens.
Greece endured a debilitating financial crisis from 2010 that required three cash lifelines from its European Union partners. The economy is the public's main concern, said Thomas Gerakis of pollsters MARC.
Tsipras says a vote cast for Mitsotakis would go to the political establishment, which forced Greece to the edge of the precipice in the first place.
"I am completely satisfied, whatever the mistakes, whatever the omissions. He got us out of the bailouts," said Niki Loufa, 61, a retired bank worker, about Tsipras.
While economic growth has returned, Greek unemployment of 18 percent is the euro zone's highest.
New Democracy has promised to invest in creating well-paid jobs with decent benefits. The outgoing government meanwhile hopes voters will reward it for upping the minimum wage by 11 percent and reinstating collective bargaining. Its leader has promised to lower taxes and social security contributions, maintain aid to the needy, attract foreign private investments and create a 'rampant' economy.