Prime Minister Kyriakos Mitsotakis' governing New Democracy party leads its nearest rival by 14.7 percentage points, according to a new poll.
The survey shows the conservatives edging back above 30% in projected support, with national elections due next year.
The Marc poll for private broadcaster ANT1 puts New Democracy at 30.5% in its vote estimate. The Greek Left Alliance, or ELAS, the new party of former Prime Minister Alexis Tsipras, is second at 15.8%. The center-left PASOK is third with 12.5%.
They are followed by the nationalist Greek Solution at 7%, the Communist Party at 6.8% and the left-wing Course of Freedom at 5.5%.
The government's lead is wide, but approval of its record is not. Only 36% rated its performance positively, while 63.5% gave a negative view.
Mr. Mitsotakis remains voters' top choice for prime minister at 31%. Mr. Tsipras has 14.7% and PASOK leader Nikos Androulakis has 7.8%.
The poll points to a tightening contest to lead the opposition. PASOK was seen as the more effective opposition party, with 19.3% compared with 9.3% for ELAS.
Respondents also preferred PASOK to lead the center-left by 38.9% to 25.7%. Among center-left voters alone, however, the two were nearly even.
More than eight in 10 respondents, or 83.4%, said they view the country's political debate negatively. About one in 10 said armed conflict with Turkey was very likely.