Until now no one has known what sort of people they are, why they joined the party and whether they are different from the existing membership. Is their vision Blair's vision? Will they go along with him in government or will they be impatient for radical change? In his speech to last year's conference, Blair himself joked: "I hear some of you support me just because you think I can win."
Evidence gathered by the Independent suggests he was right. The new recruits are the "New Pragmatists" - their views are more old Labour than new, but they support Blair because they think he will beat the hated Tories. And, because their expectations of him are limited to victory and they understand he is different from them, he may even have an easier ride in government than any of his predecessors.
The only substantial academic survey of Labour members is now seriously out of date. Patrick Seyd and Paul Whiteley of Sheffield University interviewed 5,000 Labour members in 1989-90. They had more left-wing attitudes than the leadership on nationalisation, defence and education. But there was evidence of pragmatism even then: 57 per cent agreed that Labour "should adjust its policies to capture the middle ground of politics". Mr Seyd says the new members interviewed in a follow-up study in mid- 1992 were "more supportive of electoral reform, but were not much out of line with existing members in their general attitudes". Now he admits it is "tantalisingly frustrating" not to know who the Blair intake are and what they think. "Mr Blair obviously thinks they are malleable credit- card payers, whereas the left think they are crypto-SDP-ers. We simply don't know," he says.
In March this year, the Labour Party carried out its own survey of about 1 per cent of those who joined in the previous year. It was a self-selected sample who filled in a questionnaire in Labour Party News, and told little about their views - merely that 60 per cent were men, 47 per cent were in "professional" jobs and only 29 per cent were under 35. In other words, much like existing members, only more middle-class and a bit younger.
In order to find out more, the Independent's own mini-survey spoke to a random sample of 50 people who have joined in the past year - it provides the first important clues to the identity of the New Pragmatists. Because Labour holds its conference today in a model constituency of the "new" party, we chose the Brighton Pavilion Labour Party for our survey. Membership here has risen from 900 to 1,400 since Blair was elected leader. Like the party's survey, our sample were not particularly young. Only five were students, despite a large student population in Brighton, and many were retired - joining because they now had "time on their hands".
The first truth to establish about the new members is that they are not an uncritical Tony Blair fan club. Revulsion from the Conservatives is a more powerful force than the attraction to Blair - although he is important because he both articulates that revulsion and inspires confidence that the Tories can be beaten. They are not uniformly convinced that every change and every silence is needed, yet they sense they are on a winning side.
Carlie McBride, 18, is a young New Pragmatist. Joining while still studying for her A-levels, she was inspired by one of Blair's speeches, although Blair did not deliver it. "It was at the Theatre Royal in Brighton with Sir Ian McKellen quoting from a speech Blair had given on the age of consent. It just struck a chord."
On Blair himself she is not completely convinced. "I've mixed views. I don't like everything he's saying, like he's not going to renationalise - I don't see why we should go along with that." She does not trust Blair 100 per cent, but she trusts him to "pull votes from disenchanted Tories".
McBride won an assisted place to Brighton and Hove High School, a private girls' school. From a "council estate, socialist background", the intervening years appear to have taught her "the Tories are still the party of the money-people. You vote Tory if their policies haven't touched you. If you haven't used the public health, education, transport services you don't miss them." Blair is not her favourite: "I like John Prescott, but he wouldn't win."
In the small Baker Street offices of Brighton Pavilion Labour Party, a large "Operation Victory" poster greets all who enter. But pride of place, among more modern messages such as "Socialistes Europeens pour les femmes de l'Europe", is Labour's "Now we can win the Peace" poster from 1945. The wartime flavour recalls Winston Churchill's observation that politics is as exciting as war and quite as dangerous, and according to full-time organiser Keith Day the new recruits are anxious for the real battle to commence.
"Operation Victory" for them is clear: the seat, held by Conservative Sir Derek Spencer, the Solicitor General, is Britain's 22nd most marginal.The 8 per cent winning margin between Tory and Labour in the 1992 general election has been reduced even further with a boundary change that brings in a rock-solid Labour ward. Day's confidence is increasing: "It encourages you to know that 10 people are joining the party every week."
They are joining, however, in the belief that the Labour Party stands for things which Blair has tried to make clear that it no longer does: 45 of the 50 said they wanted "higher public spending, paid for by higher taxes on the better-off". Blair and Shadow Chancellor Gordon Brown have reiterated their objective of getting the tax burden down. But for Labour joiners - as for most of the electorate - high tax and high spending are still at the core of what the Labour Party is.
Education also touches core values. Asked about Blair's decision to send his son to a grant-maintained school, "disappointed" was the middle response in a range from "it's up to him" to "disgusting"; 24 of our group responded unfavourably, 19 were neutral and only five positively supported Blair's decision.
When it comes to political strategy, the new members are strikingly flexible and deferential. Some were quite happy to change the name of the party to New Labour if Blair thought it would help win the election. Only eight actually preferred to call themselves New Labour - 33 opted for "Labour", three for "Old Labour" and three for "Socialist". "I would be prepared to change the name to New Labour if that would help further their political ascendancy," said Maureen Green, a sympathiser for 40 years.
As for Liz Davies, the rejected candidate for Leeds North-East, if Blair wanted her out, that was good enough for them. Although only 16 felt they knew enough about her to have an opinion, they divided 12-4 in favour of the National Executive's decision.
Dr James Whitehead, 33, a research fellow in social anthropology at London University, is another New Pragmatist: "Blair displays an ambiguity between needing to win power and his responsibility to the left to win votes. But he's pragmatic, a good figure at the right time." Whitehead, a member for 18 months, believes "not all promises will be delivered". But he thinks "Blair will do his best".
Guy Radcliffe, 41, a house renovator, joined because he felt "I could no longer comment without taking part". Radcliffe, who joined in May after three years abroad, came home to discover "an impressive man leading the Labour Party who worries me a little".
Feeling that Labour lacks well defined policies, wanting radical constitutional change and strong links with the trade unions, are not enough to put Radcliffe off Blair: "This man can win over disenchanted Tories. Sure, he will scare those who think he is too far to the right, but where these people will go I have no idea."
What Blair has done for recruitment is to change his party's losing image. On the doorsteps in Brighton, from students' residences, council estates, private-sector rented flats to up-market Regency and Georgian homes, Labour is seen as a potential winner. Much of the growth in membership is the product of high polling ratings and high morale. It is easier to persuade people to join a winning organisation. This is reflected in the return of lapsed members, and in the markedly higher retention rates among existing members. Keith Day says in the past about 25 per cent of the membership would lapse every year. Last year it was 5 per cent.
The Blair Effect is indirect, in that he does not necessarily inspire people to join the Labour Party but, because they think he is going to win the next election, the party has become worth joining - and not just in the short term. The new members are not merely fair-weather recruits.
It is even possible that the new recruits are more likely to stand by Blair through the inevitable disappointments of office. Ruby Besch, who finally joined the party, aged 74, says Blair "seemed the person to get rid of this dreadful government - but, while I'm optimistic, there will be problems. The finances may not be available. It is going to be difficult to turn things around."
Additional reporting by Natasha Roffe.
What Brighton's new members think about...
"I would stand with pants on my head in the middle of the town square if he thought it would make a difference." Paul Duffy
Tony Blair's decision to send his son to an opted-out school:
"As a teacher I thought it was the decision of a wimp." Caroline Driver
On the rejection of Liz Davies:
"If you want to be part of a party, co-operation is essential. The party needs to have a certain identity which will make it electable - it would do the party no favours to have another Michael Foot." Jean Taylor
"She is being totally marginalised - it is disgusting. They should have room for all types of opinion, it should be a broad church. The party has become like the left faction of the Tory party." Mary Tomlinson
On the union block vote:
"There should be further reductions - not a complete abandonment of union ideals. But certainly not the old constant stream of Seventies leaders screaming and shouting." Paul Duffy
On the new Clause IV:
"I was against it, but, with hindsight, it is a good thing." Anna Pearson
On "New Labour":
"Labour is a political party, not a washing-up gimmick. You don't buy it for the quality of its fabric conditioner." Ted Powers
"Britain's culture has changed - it is far more individualistic, the community is far less important. People are yearning for something more - even people who are earning a lot are still hungry for something more - that void could be filled by Labour." Graham Anderson