ATHENS (Reuters) – Greeks vote on Sunday in an election expected to bring in a government led by the leftwing Syriza party.

The anti-bailout party led by Alexis Tsipras is leading in the polls but it is unclear if it can win enough seats to govern without having to rely on one or more of the smaller parties.

Key Facts

• About 9.8 million Greeks aged over 18 are eligible to vote, including about 240,000 first-time voters.
• Polling stations open from 7 a.m (12 a.m. ET) to 7 p.m. An exit poll is issued immediately with first official projections from 9.30 p.m. Final results could be announced in the early hours of Monday.
• A total of 18 parties and 4 party alliances are running. They need to secure at least 3 per cent of the vote to enter parliament for a four-year term.
• Voters in Athens, where half of the country’s 11 million population live, elect 58 deputies.

Parties that may enter parliament:

• Syriza, leftwing. Leader Alexis Tsipras
• New Democracy, center-right. Leader Antonis Samaras
• To Potami (The River), centrist. Leader Stavros Theodorakis
• Golden Dawn, far right. Leader Nikolaos Mihaloliakos
• PASOK, centre-left. Leader Evangelos Venizelos
• KKE, communist. Leader Dimitris Koutsoubas
• Independent Greeks, right. Leader Panos Kammenos
• Movement of Democratic Socialists, center-left. Leader George Papandreou

Majority

The biggest party automatically wins a 50-seat premium to make it easier to form a stable government.

But the share of the vote needed to secure a 151-seat majority in the 300-seat parliament varies depending on how the overall result is divided between parties.

If all parties running get into parliament, the threshold for outright victory is just over 40 per cent but the majority drops depending on how many votes go to parties that fail to clear the 3 per cent entry threshold.

If, for example, 5 per cent of the vote goes to parties that fail to get into parliament, the margin for victory could be around 38 per cent.

If there is no outright winner, President Karolos Papoulias gives the leader of the biggest party a mandate to form a coalition or gain agreement for a minority government. Should this fail, the exploratory mandate is handed to the second party, and then to the third.

If the parties cannot agree, the president holds a final meeting with party leaders. If they still cannot agree, he appoints a caretaker government to call new elections.

(Reporting by Renee Maltezou; Editing by Raissa Kasolowsky)

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This article originally appeared at Reuters. Copyright 2015. Follow Reuters on Twitter.

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