Prime Minister Kyriakos Mitsotakis has said that his New Democracy party can win a governing majority in next year's elections, telling supporters at its 52nd anniversary event that it will again exceed 40% of the vote.
Mr. Mitsotakis said the conservative party has topped that mark in four past elections, including under his leadership.
"And we will do it again," he said. "We will belie the expectations of those who believe we can't achieve our stated target. We will do it again in 2027."
Polls show New Democracy far ahead of rivals but well short of that level. A Metron Analysis survey last week put it at 30.2% in vote estimate, while an Alco poll had it at 24.3% in raw voting intention.
At around 30%, the party would struggle to govern alone, and no other party has shown any appetite for a coalition with it.
Alexis Tsipras's new left-wing party ELAS polls second at roughly 14% to 17%, with PASOK close behind at about 11% to 13%.
Both say they hope to finish first. Mr. Mitsotakis is seeking a record third consecutive term.
"We can constantly renew ourselves," Mr. Mitsotakis said. "That is our great strength and that will allow us once again to gain Greeks' confidence."
He said the party would use the campaign to explain its plan for Greece in 2030.
He has pointed to Greece's economic recovery, falling unemployment and low borrowing costs as the basis for his case, while opposition parties cite cost-of-living pressures.
Polls also show majorities saying they are dissatisfied with the government's performance.