Government ministers will no doubt attempt to rubbish the result yesterday of a national ballot on the question of whether Britain should hold a referendum before signing the Lisbon Treaty.
The decisive vote - 88 per cent demanding a referendum and 90 per cent opposed to the treaty - will probably be dismissed along the lines of, well they would say that wouldn't they? There is an element of truth to the argument, since it is probable people opposed to the EU would be most likely to have taken the trouble to participate in a ballot organised by the I Want a Referendum Campaign.
But the Government should be careful about being too blase. Yesterday's ballot, held across 10 constituencies in England, Wales and Scotland, attracted a 36.2 per cent turnout - the highest ever for an unofficial ballot and above average for local government elections.
The figures demonstrate the suspicion about the EU which still widely exists. And while the matter of the European constitution may to a certain extent have fallen off the public opinion radar, there are clearly a great many people who view the Lisbon Treaty as an attempt to formalise the constitution through the back door and are ready to use whatever powers they possess to protest.
Government backing for the treaty, along with support from the Liberal Democrat party, makes it certain that the document will be ratified by Parliament on Wednesday, even if some MPs rebel. But the Prime Minister will know now, if he didn't before, that his refusal to hold a referendum could yet return to damage Labour's prospects at the next General Election.
The problem for Mr Brown is that, having inherited an election promise to hold a referendum on the EU constitution, most people expect him to do precisely that.