Greece’s general election has failed to produce a winner despite the centre-right party of the incumbent prime minister, Kyriakos Mitsotakis, clinching 40% of the vote with more than 90% of ballots counted. New Democracy was leading with a 20-point margin – 40.8% – over the leftist main opposition Syriza party which was trailing at just over 20.1% – a difference rarely seen since the collapse in 1974 of military rule. Even in Crete, a socialist bastion, the rightwing party had fared unexpectedly well. “It appears that New Democracy will have a very important victory,” said Giorgos Geropetritis, a former state minister and one of Mitsotakis’s closest colleagues. “The Greek people took stock of the past and voted for the future … it voted for future generations.” Other government officials described the result as a “spectacular victory”. Under a new electoral system of proportional representation introduced under the former prime minister and Syriza leader Alexis Tsipras, the victor had to secure about 46% of the vote to win an outright majority of 151 seats in the 300-member parliament. That, for any party, had been an impossible feat. With 96% of the vote counted, smaller parties including MeRa25, headed by the country’s former finance minister Yanis Varoufakis, failed to pass the 3% threshold to get into parliament. KKE, the communist party, came in with 7.2% of the vote, doing especially well in urban centres, with senior officials hailing the outcome as proof of the party’s ability to put up stiff opposition to “neoliberal” policies it has said are bringing Greeks to its knees. The inconclusive result will lay the ground for a fresh ballot in July if, as expected, efforts to form a coalition government break down. The second-round poll, expected on 2 July, will take place under a semi-proportional representation system that would grant the first party 50 bonus seats if it won 40% of the vote. On Monday, as protocol demands, Greece’s president, Katerina Sakellaropoulou, will hand Mitsotakis a three-day mandate to explore the options of forming a coalition. Aides said the 55-year-old leader, who appeared in ebullient mood as he arrived at New Democracy’s headquarters in Athens, would prefer a repeat poll with Sunday’s result hardening his view that a single-party government was “more than possible”. In an address on Sunday night the prime minister said he was “proud and moved” by the result. “Hope has beaten pessimism, unity has beaten division,” Mitsotakis said. “I pledge to work even harder. People want a strong government with a four-year mandate so that we can cover the lost ground that separates us from Europe. A government is needed that really must believe in reforms so that it can implement them.” Throughout the electoral campaign he had insisted the country’s interests could only be served with “a strong majority” government that would enable him to press ahead with his reform programme during a second four-year term. If, as looks likely, Mitsotakis hands the mandate back to Sakellaropoulou, Syriza in theory will follow suit in trying to form a coalition government, although the results did not suggest a leftist coalition would be arithmetically feasible even if leftist parties could find the consensus. It had been thought that the governing party’s popularity had been severely dented by a wiretapping scandal and devastating train crash – events that cast a pall over Mitsotakis, a former banker, personally. But Syriza’s unexpectedly poor performance appeared to uphold the view that Greeks had voted for stability – despite many being perturbed by what has been perceived as democratic backsliding under the centre-right government, with the spy scandal highlighting those concerns. In an election dominated by anxiety over the cost of living crisis, Greeks singled out the economy, citing memories of the nation’s debt drama a decade ago and punishing austerity meted out in return for emergency funds to keep the country afloat. Sunday’s ballot was the first since the EU and IMF, which orchestrated the biggest bailout in global financial history to avert a Greek default, ceased supervising the country’s finances. But trauma still lingers. The cuts demanded in exchange for rescue exacted a heavy price: the Greek economy contracted by more than 25%, beginning a recession from which the nation has only begun to recover. “The idea of more adventures after everything we have been through swayed my vote,” said Maria Lygera, echoing a common refrain. The 48-year-old was among a sizeable cohort of undecided voters estimated at close to 13% before polls opened. “Right until I walked into the ballot booth I wasn’t sure which way I would go,” she said. “I wanted to punish New Democracy because of the wiretapping scandal but equally I also wanted to ensure there is a centre-left party that is present and strong. Because that is definitely not Syriza, I voted Pasok.” The Pasok party came in third with just under 12%, a result its jubilant leadership said placed it on course to replace Syriza as the main centre-left opposition. Mitsotakis has promised to cut taxes further, bring down unemployment – hovering about 11%, from an all-time high of 30% during the crisis – and stimulate the economy by attracting more foreign direct investment. His election campaign motto has been “stability”, with the politician evoking the turbulence of Syriza’s time in office when Tsipras, its firebrand leader, was catapulted into power in 2015. Tsipras, 48, has toned down the radical rhetoric that first appealed to his base but throughout the election campaign vowed to raise public sector wages to help assuage the effects of the cost of living crisis and upgrade state facilities including the public health system. Senior Syriza cadres described the outcome as deeply disappointing and a far cry from what the leftwing party had hoped to achieve. “The result is extremely negative for Syriza,” Tsipras said on Sunday night, announcing immediate changes in the party. More than 9 million Greeks were eligible to cast ballots in a vote held under a rarely used proportional representation system. In an historic step Greeks abroad were also able to participate at polling stations set up in the UK and cities across Europe, the US, Canada and Australia. Voter turnout was said to be high among the more than 22,000 diaspora Greeks registered on the electoral roll. But from the outset the new electoral procedure had made it practically impossible for any candidate to win the 46% required to form a single-party government. Not since 1981, when Andreas Papandreou charged to victory on the slogan of allagi or “change”, has that feat been pulled off. With such high probability of the result being inconclusive, Mitsotakis had raised the spectre of a follow-up election in July even before Greeks began to cast their ballots.