When the result of the Irish Republic's referendum is announced on Friday afternoon, and if it amounts to nul points for the Lisbon treaty, there will be only one name on the lips of defeated eurocrats: Declan Ganley.

A multimillionaire entrepreneur, devout Catholic and father of four young children, Mr Ganley is the son of Irish emigrants who struggled to return to Galway from England as soon as funds permitted.

He has never been involved in politics but his barnstorming campaign against the treaty has set teeth on edge in the “yes” camp presided over by Brian Cowen, the Taoiseach.

Ireland is the only EU member state where the Lisbon treaty, which charts the next steps in European integration, has been put to a referendum. An Irish “no” would threaten to scupper the project.

While Mr Cowen, the Fianna Fáil leader, assisted by his allies in the opposition parties, was winding up the last official day of campaigning with a message that strove to combine calm rationality with a hint of menace at what Brussels might do to Ireland if it throws out the treaty, he could not resist a dig at Mr Ganley where he is perhaps most vulnerable: in his deep and well-upholstered pocket.

Mr Cowen said in a radio interview that people should question where the money was coming from to fund the “no” campaign.

Almost a month of campaigning has left Mr Ganley more than able to bat the question aside. “It's the classic ‘when did you stop beating your wife?' tactic, regardless of the fact that we are spending minuscule amounts compared to the “yes” campaign,” he told The Times.

“We have answered it ad nauseam. We are getting donations primarily from the business community but we have had taxi drivers and grannies giving money as well.”

The question is seemingly pertinent because of the vast fortune he built from trading Russian aluminium, Latvian forestry and Eastern European telecoms and the rather crude attempts during the campaign to portray him as a stooge for the US military-industrial complex. Most of his business is now in the United States, where he sells emergency response equipment, from firefighting appliances to blankets, for which he was awarded a distinguished service medal by the state of Louisiana for his efforts during Hurricane Katrina.

“You won't read that anywhere in the Irish media,” he comments drily in an English accent, the product of spending the first 13 years of his life in Watford. RTE, the state broadcaster, is “nakedly biased” in its coverage of the campaign, he says.

The question he refuses to answer is what happens after Friday's result. Win or lose, he has built a public profile from zero and it seems unlikely that he is about to disappear into the background. “Let's talk about that after the result. Right now it's eyes on the prize. I'm an entrepreneur, a businessman, let's get it done.

“But there's a lot of people out there across Europe who have had enough. We want a European Union that's credible but we're sick of the failure of this Brussels elite to bring the people with them - it almost seems like some sect of secular cardinals who think they know better than us.”

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