Socialist MEP Paul Murphy, who is advocating a 'No' vote in the Fiscal Treaty referendum, has said it is all still to play for despite a Red C poll on behalf of the Sunday Business Post indicating increased support for the treaty.
The survey shows a six-point gain for the 'Yes' side of the treaty debate to 53%, while the 'No' side has dropped four points to 31%.
But Mr Murphy has said the Government's scare tactics will wear thin with electorate.
Mr Murphy said: "The government's campaign up until now has consisted overwhelmingly of scaremongering about access to second funding. This seems to have had some impact.
"I have met many people who are opposed to this Treaty but are scared about the dire consequences promised by the government in the event of a No vote.
The same survey also shows that Fine Gael's support is down to 29%, and Labour is back at 13%.
The Socialist MEP said: "However, the simultaneous decline in support for both government parties suggests that the rise in Yes support can be dramatically reversed whenever it becomes clear that the scaremongering is simply more lying by the government, just as it lied about jobs in the second Lisbon referendum."
Mr Murphy claimed that there is an increasing uncertainty about the treaty across Europe which is likely to deepen in the coming weeks, and he said it "will work against the Yes camp".
He said: ""It will become clear to people that the vote in Ireland will have a vital impact on whether this Treaty comes into being or not, given the ratification's shaky status in many countries around Europe.
"This will sharpen minds in the coming weeks. People may choose to join in the Europe-wide struggle against austerity by helping to sink this Treaty on 31 May."