Main opposition New Democracy conservative party leader Mitsotakis addresses supporters during a pre-election rally in Athens
Main opposition New Democracy conservative party leader Mitsotakis addresses supporters during a pre-election rally in Athens.

Conservative Greek opposition leader Kyriakos Mitsotakis rode to a landslide victory over leftist Prime Minister Alexis Tsipras in Sunday's parliamentary elections and is set to become the country’s new head of government Monday.

Tsipras, rejected as the Greek leader after four years, said he called Mitsotakis, the son of a former prime minister, to congratulate him on his victory.

A combined survey of Greece's main TV stations showed Mitsotakis's New Democracy party leading Tsipras' Syriza party by an average of 39.8% to 31.6%. If the trends hold, the 51-year-old Mitsotakis, a graduate of Harvard in the U.S., would have a 158-seat majority in the 300-member parliament.

People walk past a poster depicting Greek PM Tsipras at the election kiosk of the leftist Syriza party in Athens.

The 44-year-old Tsipras, Greece's youngest premier in more than a century, had trailed for months in pre-election surveys, with voters voicing widespread dissatisfaction over high taxes.

Greece is just beginning to recover from a massive financial crisis that included soaring unemployment and steep poverty levels. The country was forced to accept billions of dollars in financial bailouts from the International Monetary Fund, other eurozone countries and the European Central Bank that required deep spending cuts and other reforms.  

Mitsotakis has pledged to create "better" jobs through foreign investment, tax cuts and removing obstacles for businesses.