Patricia Callan, director of the Dublin-based Small Firms Association (SFA), admits she is nervous about the outcome and refuses to rule out the possibility that the “no” campaign will pull off another surge and emerge triumphant again on October 2.

She told the Sunday Herald: “The ‘yes’ side was even further ahead at the same stage last time, so we can’t afford to be complacent. We’re going to have to campaign right up to the wire.”

Although the economy has dominated debate far more than in the summer of 2008, a raft of other issues – military neutrality, abortion and the fate of Ireland’s EU commissioner – continues to crop up. The worry for business is that many voters will use the vote to punish Taoiseach Brian Cowen’s unpopular government.

Popular support for the ruling Fianna Fail has plunged to a historic low of 23% as it has struggled to deal with a slump that is among the worst anywhere in Europe. It may plunge still further following the announcement five days ago by finance minister Brian Lenihan that he will authorise €54 billion of taxpayers’ money to try to neutralise the Irish banks’ toxic loans.

It is the biggest gamble since the foundation of the Free State in 1922 and comes as unemployment is soaring and the government is slashing public expenditure to try to plug a €25bn fiscal deficit for this year. The fact that Bank of Ireland and AIB share prices rebounded on the back of the minister’s announcement may only fuel further public anger – anger which some may vent by recording a “no” vote on October 2.

A recent SFA survey showed that three out of every four small firms believe that a second rejection of the treaty could negatively impact small businesses and jobs. As well as ­worrying that cutting deals on the Continent could become harder, 78% fear for Ireland’s continued ability to attract foreign investment if four million

Irish citizens are seen to block closer integration for a community of 499 million citizens.

Commenting on the survey, Dr Aidan O’Boyle, the association’s chairman, said: “The multinational sector, as well as being an important creator of jobs in Ireland in its own right, is also critically important to the rest of the economy since multinationals drive economic growth and contribute to domestic demand, which is essential for all other domestically trading small businesses.”

The EU is by far Ireland’s most important trading market, representing almost two-thirds of its total exports. The volume has almost doubled since the single market was established in 1997, reaching an annual value of €95bn in 2008. There are now 198,000 people directly employed by companies exporting to the rest of the union and a further 200,000 jobs being provided through sub-suppliers and related activities.

These statistics have been getting trundled out regularly over the last few weeks by the Irish Business & ­Employers Confederation (IBEC), which contends that Ireland is already paying a heavy price for reputational damage among international investors.

IBEC’s director of EU and international affairs Brendan Butler added: “At a time of great economic turbulence, a question mark hangs over our reputation and our relationship with Europe.

“By removing the uncertainty that currently exists, a ‘yes’ vote will ensure that Ireland remains an ­attractive location for foreign investment. It will be a very positive step towards getting Ireland firmly on the road to recovery.”

Dublin’s big problem is that there are no green shoots to point at on the emerald isle. Consequently, Irish people’s confidence in their economy has plummeted to the lowest levels in Europe, with just 6% rating the ­country’s performance positively. Only Hungarians and Latvians are gloomier.

Anticipating a personal bloody nose, Cowen has been urging compatriots to think about long-term domestic economic interests. Speaking at the formal launch of his party’s campaign for a “yes” vote, the embattled premier said: “The simple fact is that a rejection of this treaty after receiving comprehensive assurances to our concerns would be seen by many as Ireland moving away from the core of the EU. There is no conceivable economic benefit which would come from this and there is undeniable potential for long-term damage.”