DUBLIN (Reuters) - Plans to reform the European Union's creaking institutions could be thrown into disarray when Irish voters go to the polls on Thursday for a referendum on the Lisbon treaty.
Latest polls show the "No" camp building support ahead of the poll, with one survey in the Irish Times last week showing opponents of the reform treaty in the lead for the first time.
Growing opposition has sent shock waves through Brussels where policy chiefs fear a "No" from one of the smallest countries in the 27-nation bloc would derail the replacement for a constitution rejected by French and Dutch voters in 2005.
The treaty will create a long-term president of the European Council of EU leaders, a stronger foreign policy chief, a more democratic voting system and give a greater say to national and European parliaments.
Ireland is legally bound to hold a referendum because the treaty affects its constitution. That means voters in a country accounting for less than 1 percent of the bloc's 490 million strong population hold the pact's fate in their hands.
Ireland has been a member of the European Union for 35 years, enjoying faster economic growth than any other member and emerging from the historic shadow of British dominance.
But that success has not been enough to guarantee the success of a "Yes" campaign backed by Ireland's three biggest political parties, congress of trade unions, business confederation and powerful farming lobby.
The treaty's supporters stand accused of failing to make their case in the face of opposition from a loose but vocal coalition of opponents.
"The campaign has not been well run by the 'Yes' side," Brendan Butler, director of strategy for the pro-treaty Irish Business and Employers Confederation, told Reuters.
"They have tended to spend their time back-pedalling and trying to offer rebuttals to points made by the "No" side."
The "Yes" camp has had to contend with pacifists who fear Ireland's military neutrality will be compromised, anti-abortion groups who say strict Irish abortion laws risk being diluted and nationalists who argue small countries will lose influence.
A handful of businessmen has also warned control over tax policy will be lost to Brussels and almost all opponents say the treaty fails to give enough power to elected representatives.
The government. led by new Prime Minister Brian Cowen, accuses opponents of scaremongering by campaigning on issues that are unaffected, or at least safeguarded, by the treaty.
Indeed ministers have argued that the pact's biggest problem is a lack of radical measures likely to enthuse voters.
"It's very difficult for them to tangibly say why people should vote yes," said Richard Colwell, Managing Director of pollster Red C Market Research. "Saying it's about making the EU work better is not very compelling for the bloke on the street."
The main weapon remaining to treaty supporters has been a carrot-and-stick appeal to people's pro-European instincts.
The slogan "Good for Ireland, Good for Europe", coupled with warnings that rejection would have dire economic consequences and isolate Ireland diplomatically, have some resonance given EU support underpinned the country's Celtic Tiger economic boom.
"Ireland is a small country in a big world," said mother of six Louise Byrne as she took a rest from shopping in Dublin. "I don't want us left isolated in one wee corner of the world."
Some voters feel patronised by such warnings, however.
"I immediately take a step back when I am being told that the sky will fall if I vote 'No' because it simply isn't true," said 39-year-old writer Mary Kate O Flanagan who grew up in Denmark and described herself as very pro-European. "The 'Yes' campaign is being orchestrated using veiled threats and fear."
Prime Minister Cowen, who is enjoying healthy opinion poll ratings after one month in office, believes he can still win if the country's main political parties can persuade their supporters to turn out and vote.
Ireland almost derailed plans to expand the bloc eastwards in 2001 when voters initially rejected Europe's Nice Treaty in a vote where the "No" camp turned out in strength but just 35 percent of the total electorate voted.
Opinion polls show that this time round those most likely to vote on Thursday are also more likely to vote "Yes".
"Certainly Cowen's party has seen a big boost since he was elected," said Red C's Colwell. "Given that his supporters are likely to back him that is a positive for the treaty."
For more stories on the referendum, visit: uk.reuters .com/news/globalcoverage/EUreferendum
Additional reporting by Andras Gergely; editing by Keith Weir