Greek Prime Minister Kyriakos Mitsotakis, leader of the conservative New Democracy party, delivers a speech to his supporters during the party's main campaign rally in Thessaloniki on June 21, 2023, ahead of Greek legislative election. (PHOTO / AFP)

ATHENS – Former Prime Minister Kyriakos Mitsotakis' conservatives appear set to win a repeat election in Greece on Sunday after an inconclusive vote on May 21, putting him back in office.

Mitsotakis's New Democracy party won in May, 20 points clear of the leftist Syriza party that ruled Greece from 2015 to 2019, but fell just short of the outright majority needed to rule without forming a coalition, prompting the second vote.

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Sunday's election is being held in the shadow of a migrant shipwreck on June 14 in which hundreds of people are feared to have perished. One of the worst migrant disasters in years, it has shown the parties' divisions over migration.

Sunday's election is being held in the shadow of a migrant shipwreck on June 14 in which hundreds of people are feared to have perished. One of the worst migrant disasters in years, it has shown the parties' divisions over migration

Opinion polls show New Democracy with more than 40% percent of the vote, with Syriza headed by Alexis Tsipras trailing at about 20%. Mitsotakis, prime minister since 2019, stepped down in favour of a caretaker premier following the inconclusive May vote as required by the constitution.

Analysts said a row over who was to blame for the shipwreck had likely slightly boosted Mitsotakis, who tore into his arch rival Tsipras for suggesting Greece didn't do all that it could to prevent the disaster.

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"(The debate) has helped New Democracy because Syriza's first, instinctive reaction was to voice doubts over the coast guard (and its handling), while New Democracy appeared to be protecting the borders," said Apostolos Pistolas, a voting behaviour analyst.

Rescuers found 104 survivors but up to 750 people were thought to have been packed on the ramshackle vessel that had sailed from Libya and was heading to Italy. The boat had been shadowed by the Greek coast guard before it sank: the coast guard has said that the occupants refused all offers of help.

Mitsotakis, whose administration has taken a hard stance on migration, said "wretched traffickers" were to blame for the disaster and praised the coast guard for rescuing people.

Supports of the main opposition Syriza party listen their party leader Alexis Tsipras, during a pre-election rally, in Athens, on June 22, 2023. Greeks heading to the polls on June 25. (PHOTO / AP)

Tsipras has questioned why the coast guard did not intervene earlier. Under the previous Syriza administration, more than one million refugees and migrants reached Greek islands as they tried to come to Europe in 2015 and 2016.

The disaster sidelined other issues in the run-up to the election, including a cost of living crisis, and a deadly rail crash in February that exposed shortcomings on the public transport system.

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REPEAT VOTE, DIFFERENT RULES Sunday's vote takes place with different rules to the May election – the front-runner wins bonus seats in the 300-member parliament allowing it an absolute majority.

Behind the bigger names are a number of smaller parties, including MeRA25, headlined by Yanis Varoufakis, a former finance minister noted for unconventional tactics at the peak of Greece's debt crisis a decade ago.

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Leftist Zoe Konstantopoulou, another veteran of Greece's turmoil remembered for making hours-long speeches ripping into Greece's lenders while speaker of parliament, is also seeking a seat.

Also running are the Spartans, named after the formidable warriors of Sparta in ancient Greece, who say the country is threatened by uncontrolled migration.

The nationalist group was catapulted from relative obscurity after support from Ilias Kasidiaris, a frontman of the now-banned Golden Dawn far right party. He is currently in jail.