By Nick Assinder
Political correspondent, BBC News website
Tony Blair's decision to hold a referendum on the original EU constitution was one of the bigger climb downs of his premiership.
For months he insisted there was no need for such a vote, but he was eventually overwhelmed by the demands and, apparently fearing a backlash in the 2005 general election, he caved in and included a pledge to that effect in the Labour manifesto.
Gordon Brown is resisting referendum demands
The question now being asked is whether Gordon Brown is being pushed down the same road with the EU treaty which was put together after the constitution was rejected in referendums on the continent.
The Opposition is demanding a poll on the treaty and David Cameron has pledged to force a vote in the Commons on the issue in an attempt to embarrass Gordon Brown with a backbench rebellion.
He has been encouraged in that move by the fact that a number of Labour MPs have joined an all-party referendum campaign.
However the announcement by Liberal Democrat leader Sir Menzies Campbell - to the irritation of some in his own party - that a referendum is unnecessary, has taken some of the heat off Mr Brown.
None the less, Mr Cameron clearly believes he is on to a winner here, just as his predecessors were with the last referendum campaign.
Anger at rebels
His approach seems to echo a growing public mood, it will certainly please some of his right-wingers, he can use it to embarrass the prime minister and allegedly broken manifesto promises and it gives him something simple and distinctive to campaign on.
Meanwhile the unions, led by the GMB and RMT are backing the demands, believing the new treaty could threaten their members' rights and encourage more privatisation of public services.
They are angry that former prime minister Tony Blair negotiated an opt-out from the charter of fundamental rights, which increased union rights to industrial action in the other 26 EU countries.
And, whatever the outcome of the TUC conference when they vote on the issue on Wednesday, they appear unlikely to abandon their position.
The Labour rebels include Gisela Stuart, who was a delegate to the original convention which helped draw up the original constitution, which was rejected by referendums in France and Holland in 2005.
Former Europe minister Keith Vaz has also added his voice to the demands, claiming Mr Brown would win a referendum.
Mr Cameron accuses government of broken promises
Other Labour MPs, however, are furious at the rebels' behaviour, claiming they are handing a weapon to the Tories and those anti-EU groups who, they claim, would turn the referendum into a vote on withdrawal from Europe.
They stress the treaty is not the same old constitution - as often claimed by its opponents - and that, as the prime minister insists, the UK's "red lines" negotiated by Tony Blair at the June EU summit - on areas including national security, justice and social services - have been protected.
Easier to win
Mr Brown has suggested if those red lines were crossed in the forthcoming EU summit then a referendum might be on the cards.
But that is seen more as a warning to other EU leaders not to push him on them than a sop to the campaigners.
But his case has not been helped by some other EU leaders suggesting the treaty retains most of the rejected constitution.
All this has led to some suggestions Mr Brown has put the treaty into his own general election calculations - even that he might call them both on the same day this autumn.
Neither of those seems at all likely and Mr Brown is not at the moment under the same electoral pressures as his predecessor.
Neither is it yet clear just how solid and widespread the referendum campaign will become, or how many Labour MPs will finally put their names to it.
The prime minister seems to be calculating that, once the final treaty is agreed at the Lisbon summit in October it will be easier for him to win his case.
None the less, the issue seems to be stacking up into one of the bigger challenges for the prime minister, just as it was for his predecessor.