ATHENS (Reuters) - Former Greek prime minister Alexis Tsipras's leftist Syriza party said on Thursday it remained confident of winning an outright victory in a Sept. 20 election despite an opinion poll that showed its main conservative rival edging ahead.
Just a few weeks ago, a Syriza victory in the snap election had appeared almost certain as Greeks lauded the charismatic and youthful Tsipras for waging a bruising battle against European and International Monetary Fund creditors over austerity cuts.
But opinion polls over the past week have shown the New Democracy party run by Evangelos Meimarakis catching up quickly, with one showing it even overtaking Syriza, suggesting a surprisingly tight contest.
A senior Syriza official played down New Democracy's sudden spurt of momentum, reiterating his party's ambition to win an absolute majority in parliament which was the hope that propelled Tsipras to call the snap vote after clinching a bailout deal with the country's creditors.
"Our objective continues to be an outright majority in parliament and in this case we would want to team up with the Independent Greeks," Panos Skourletis, a former energy minister and close aide to Tsipras, told Mega TV, referring to Syriza's former right-wing coalition ally.
He reiterated Syriza's stance against an alliance with New Democracy. By contrast, the conservatives have said they are open to a broad alliance to help steer Greece through its worst post-war economic crisis.
According to the GPO poll published on Wednesday, Syriza's stance is not backed by most Greeks: 59 percent of respondents preferred a coalition administration over a one-party government.
The poll also showed Syriza set to win 25 percent of votes, just behind New Democracy on 25.3 percent. More than one in 10 voters remained undecided, meaning the final outcome is far from certain.
A separate poll by Pulse, published on Thursday, showed Syriza clinging to a slender lead of 25.5 percent against New Democracy's 25 percent.
Tsipras defended his move to call early elections, saying that even if the rebels in his party had not toppled his government he would have still opted for a fresh mandate.
"A clear win by Syriza will be the final hit on the old political system," he told Greek Kontra TV in an interview. "What we are asking for is a clear majority mandate. If we are not given a majority, voters should render possible a collaboration on our terms."
The biggest surprise in Wednesday's poll was that Meimarakis, 61, a centrist figure within New Democracy who only took the conservative party's reins in July and has since tried to unite its various factions, was more popular than Tsipras.
"I do not underestimate Mr. Meimarakis as an adversary," Tsipras told Kontra TV. "But I want this to be a confrontation of arguments."
Meimarakis was shown with 44.3 percent approval ratings, compared to Tsipras's 41.9 percent, a major reversal for the leftist leader, who had enjoyed ratings of up to 70 percent while he battled foreign creditors over a new bailout program.
Tsipras ultimately backed down and accepted a bailout and tough austerity policies in exchange for aid under the threat of a Greek exit from the euro, but only after shutting banks for three weeks and imposing capital controls to stop Greeks rushing to withdraw their bank deposits.
Polls now show most Greeks disapproved of how Tsipras, 41, managed the negotiations with creditors and of the final outcome which was a bailout considered tougher than the previous two.
Meimarakis has benefited from keeping a low profile and is seen as a safer option among many Greeks disillusioned with their political choices, pollsters say.
"When it comes to undecided voters and they are asked who can solve most of Greece's problems, Meimarakis is favored," said one pollster, who declined to be named because the findings had not been published yet.
Syriza was favored for tackling corruption and tax evasion but on other issues such as the economy and immigration, Meimarakis was preferred, the pollster said.
Meimarakis, a former speaker of parliament, has focused his election campaign on an offensive against Tsipras and asking voters to consider the cost of the three-week bank shutdown and subsequent downward economic spiral under the leftist leader.
"I'm addressing the citizens who voted for Syriza, or abstained, telling them that they voted in protest but that the cost for that was really high. Is it really worth voting for Syriza again?" Meimarakis said during a campaign stop in Crete late on Wednesday.
"In seven months, the Syriza government has made things much more difficult for Greeks, in every sector."
Writing by Deepa Babington and Matthias Williams, editing by Gareth Jones