By Kate Holton and Kylie MacLellan
WITHAM, England (Reuters) - Striding through a housing estate in the drizzle to hand out leaflets, 52-year-old builder Kevin Lovett throws up his arms in despair as he rails against the deceit he sees at the heart of the European Union.
Whether knocking on doors or berating the EU as a corrupt superstate, those campaigning for a British exit, or "Brexit", at a referendum expected in June are driven by a passion that may be their greatest strength and their greatest weakness.
Pitching their dream of a proud Britain breaking free from a German-dominated bloc, the "Out" campaigners cast leading pro-Europeans as members of an out-of-touch elite.
But their movement has no overall leader and is made up of a jumble of bickering groups with very different visions of Britain's fate outside the EU. A battle for control and money at the top of the organization worries ground troops like Lovett.
"At the ground level we're all united and working together because we just want Britain out," he said, delivering leaflets in the pretty town of Witham in the south east of England, dotted with black and white buildings and red-brick town houses.
"I've never known people to be more engaged. The fighting at the top is what we're trying to get away from with Brussels - the politics, the meddling, the interference. This isn't about politics, this is much bigger than that."
With Prime Minister David Cameron expected to launch the official referendum campaign later this month, the leave side has limited time to unite.
A cartoon in the Times newspaper this week called "The Leave Campaign So Far" depicts a group of people screaming "You Leave", "No You Leave" at each other.
Some local leave campaigners told Reuters they were frustrated by the infighting but energized by the battle ahead. Polls show Britons roughly evenly split with a large number of undecided voters.
The main dispute in the movement is between Leave.EU, based in the south-west of Britain and focused on the grassroots level, and Vote Leave, a London-based organization run by a campaigner for lower taxes, Matthew Elliott.
Although Leave.EU secured the backing of Nigel Farage, the leader of Britain's long-established UK Independence Party, Vote Leave was seen as the group more likely to win wider support with its message of prosperity outside the EU.
The two groups have been vying to be chosen by the electoral watchdog as the official 'out' body - giving them access to public money, advertising time and greater campaign spending limits. At the heart of the split is a fundamental difference over what Britain should look like outside the EU.
Critics say the campaign is divided between those who want Britain to be free to reduce immigration and those who want rid of EU social laws so Britain can become a free trading nation fit to compete with the most dynamic countries in the world.
Stephen Booth, co-director of think-tank Open Europe, said the direction the campaign takes would determine whether it could win, and pull Britain out of a club it joined in 1973.
The different factions can speak to different parts of the electorate, he said, but in order to give a professional image they need to join forces and select a leader who can reassure voters when the 'In' camp warns about the dangers of voting out.
IMMIGRATION OR MONEY?
Leave.EU is bankrolled by a group of millionaires including Arron Banks, a British insurance tycoon who dismisses Cameron and finance minister George Osborne as "two toffs together". He told Reuters last year that the migration crisis could play into his hands, turning Britons away from the bloc.
Vote Leave argues that rather than focus on immigration, the campaign to leave needs to focus on the wider benefits Britain could get from leaving what it sees as an overly bureaucratic EU, building new free trade deals around the world.
Douglas Carswell, UKIP's only lawmaker in parliament and a backer of Vote Leave, said the campaign needed to adopt this approach if it was to reach undecided voters who may switch off from the same old message about immigration.
"I believe we need an optimistic, internationalist campaign based on the idea that we would be better off out economically."
Simon Usherwood, a senior lecturer in politics at the University of Surrey who specializes in euroscepticism, said if the 'leave' campaign could resolve its problems at the top, its campaigners were well drilled in arguing against the EU.
"The leave campaigns have been able to build on two decades if not more of practicing their message," he said. "They know what works, they know what resonates, they have got that nailed down pretty well. They have done it time and again."
Sitting in her small office in Bristol, Leave.EU CEO Liz Bilney holds a pile of letters and emails sent by supporters. "People do seem to be a little bit anti-Merkel," said Bilney, referring to the German chancellor.
She would rather recruit people like Lovett and local ambassadors - judges, doctors and teachers - than a high-profile leader.
According to Lovett, the argument needs to be made that the EU represents the needs of big business and an elite that has little interest in the lives of ordinary men or women.
Mass immigration, he said, drives down wages to the benefit of big corporations.
"We will be told by 100 company directors that we should stay in," said Lovett, as he pounded down another side street.
"But it's not their kids on the local housing waiting list, it's not their kids trying to get into the local school and it's not their wages that have been driven down. It's these people," he said, pointing to the small houses on a nearby estate. A torn England flag fluttered in the damp air.
"It is the deceit of the whole thing that gets me."
(Writing by Kate Holton; editing by Guy Faulconbridge and Janet McBride)