Greece's ruling conservative government scored a major victory in runoff local elections Sunday, emerging the winner in 30 out of 54 districts, including the mayor's race in the northern port city of Thessaloniki, DPA reported. Voters took to the polls throughout the day to elect seven regional districts and 247 municipalities across the country, in what was viewed a key mid-term test for the right-wing New Democracy party of Prime Minister Costas Karamanlis. The New Democracy party, which was elected to power in 2004 after nearly two decades of Socialist rule, also lead in the first-round ballot on October 15, emerging the winner in 28 districts compared to 19 won by the Socialists. According to official results, New Democracy candidate Vassilis Papageorgopoulos was re-elected mayor of Thessaloniki, while Andreas Fouras, backed by the main Socialist party, was elected the mayor of the western port city of Patras - the country's fourth largest city. The Socialists had hoped to win both important port cities on Sunday after coming out the clear winner last week in the Greek harbour city of Piraeus. Former basketball star Panayiotis Fassoulas earned 45.2 per cent of the vote on October 15 to oust conservative Pireaus mayor Christos Agrapidis after two terms in office. Meanwhile in Greece's capital Athens, former health minister Nikitas Kaklamanis will continue a 20-year conservative reign after beating socialist former interior minister Costas Skandalidis with 46.5 per cent.