By Dina Kyriakidou and Renee Maltezou
ATHENS (Reuters) - Greece's conservative leader begins a frantic hunt on Monday for partners to forge a coalition that preserves the country's place in the euro zone after austerity-weary voters rejected the two ruling parties in an election.
With counting from Sunday's vote almost complete, conservative New Democracy and Socialist PASOK, who have dominated Greece and are the only major parties supporting an EU/IMF bailout program that keeps Greece afloat, won just over 32 percent of ballots and only 149 out of 300 parliament seats.
After taking the largest share of votes, New Democracy leader Antonis Samaras is expected to get the first shot at forming a government. But with PASOK beaten into third place, the two must woo one of the five parties opposed to Greece's latest bailout package if they are to renew their partnership.
With Greece's parliament set to be the most fragmented for decades, coalition talks look difficult and could raise the possibility of a new election as soon as next month if they fail.
If they succeed, any coalition in the new parliament - that now includes the extreme-right Golden Dawn party - is expected to be short-lived, plunging Greece into political uncertainty and threatening to revive Europe's debt crisis.
As results trickled in, Samaras called for a pro-European national unity government that would keep Greece in the euro zone. PASOK leader Evangelos Venizelos also called for a unity government, saying his party had paid the price for handling the sovereign debt crisis.
The small parties that gained are against the bailout, but are too divided to form an alternative coalition.
"There is a lot of uncertainty at the moment about what kind of government there will be and if it will be supportive of the EU/IMF program," Diego Iscaro from IHS Global Insight said.
"LIVING AS BEGGARS"
The once mighty PASOK was pushed into third place by the anti-bailout Left Coalition party, in a vote against austerity policies that have caused deep hardship.
New Democracy polled just below 19 percent and PASOK a humiliating 13.2 percent, while the anti-bailout Left Coalition captured 16.8 to emerge as one of the night's biggest winners.
In the 2009 election, PASOK won a landslide victory with 43.9 percent against New Democracy's 33.5 percent, and the Left Coalition had just 4.6 percent.
"I cannot take it any more, living as beggars in our own country. The Left Coalition can shake them up, and wake them up," said Kate Savvidou, 65, a pensioner who deserted PASOK.
Left Coalition leader Alexis Tsipras, at 37 Greece's youngest political leader, hailed the peaceful revolution and said German Chancellor Angela Merkel should realise that austerity policies had been defeated.
"Greek people gave a mandate for a new dawn with solidarity and justice, instead of barbaric bailout measures," he said.
In another indication of the extent of public anger, the ultranationalist Golden Dawn - which denies it is neo-Nazi - was poised to take 7 percent of the vote.
This would be the first time such a party had entered parliament since the fall of a military dictatorship in 1974.
"I'm shocked they got into parliament. I wasn't expecting it, it's frightening. I think it was an irresponsible vote. We Greeks aren't fascists," said 74-year-old Panos Alexopoulos.
Under the constitution, Greek President Karolos Papoulias will give the biggest party three days to form a government. If it fails, the next largest groups get a chance. If they all fail, new polls would be called about three weeks later.
Greece faces an acid test as soon as next month when it must give parliamentary approval for over 11 billion euros (8.86 billion pounds) in extra spending cuts for 2013 and 2014 in exchange for more aid from the European Union and International Monetary Fund.
That looks like a tough task even if a new government can be formed in time. Several analysts said the unprecedented fragmentation of the vote could mean weeks of instability and force another election.
Othon Anastasakis, director of southeast European studies at Oxford University told Reuters: "Greeks are sending a very strong message abroad, which is enough with austerity."
As they voted, many Greeks expressed their rage at the parties who accepted the harsh conditions of two bailouts that have kept the country from bankruptcy.
"I voted for Left Coalition, even if this means elections again in a month. I feel vindicated. Things are changing little by little because people decided to speak up," said 22-year-old student Klelia Avgerinopoulou.
THREATS IGNORED
The Greek electoral shock coincided with the victory of Socialist Francois Hollande in France's presidential election and was likely to add to pressure for resistance to German-led austerity policies.
Italian technocrat Prime Minister Mario Monti, who faces increasing resistance to austerity at home, phoned Hollande and other European leaders after the election results to push for pro-growth policies.
International lenders and investors fear success for the anti-bailout parties could push Greece to renege on the terms of the program, risking a hard sovereign default and dragging the euro zone back into the worst crisis since its creation.
Euro zone paymaster Germany has said there would be "consequences" to an anti-bailout vote. The EU and IMF insist whoever wins the election must stick to austerity if they want to receive the aid that keeps Greece afloat.
But many voters bitterly dismissed the threats.
"I don't think that voting for a small party will make us go bankrupt. We already are," said 53-year-old Panagiotis, a craftsman, after voting for the conservative Independent Greeks.
(Additional reporting by Harry Papachristou, Karolina Tagaris, Deepa Babington, Ingrid Melander, Lefteris Papadimas and George Georgiopoulos.; Writing by Dina Kyriakidou and Deepa Babington; Editing by Elizabeth Piper)