The conventional wisdom is simple. When the votes are tallied after this Thursday's local and European elections the result will broadly be this: Tory voters desert in droves to Ukip, the Liberal Democrats are annihilated across large swathes of the country while Labour do unspectacularly well - almost by default.
Typical of this trend should be Southampton. It is a city run by Labour for the past two years, with two sitting Labour MPs fighting an election in wards where the Liberal Democrat vote has collapsed. Conventional wisdom should see Ed Miliband’s party clean up.
But that’s not how it feels on the ground.
Take Ted and Margaret Harmer. The retired carpenter and his wife have previously supported Labour – but not this time. They’ll be voting Ukip.
“The country is full up with everybody coming in,” says Mr Harmer. “It’s not England any more. I’ve voted Labour in the past but they promise and promise and never do. All I’ve got left is Ukip.”
His wife, Margaret, will also vote Ukip. She’s upset because she doesn’t get a full pension because she took time off work to look after her children – while immigrants can claim benefits.
“It’s not right,” she adds.
Or take Sarah Everitt. Her complaint is the 14 foreign children in her daughter’s class – some of whom have difficulty with English.
“The teachers spend more time with these children than the rest,” she says. “And they get housing straight away unlike the rest of us.”
Both Ms Everitt and the Harmers should be solid Labour supporters – or at the very worst not vote at all.
But, instead, they typify a problem that some Labour strategists are increasingly concerned about – that Ukip may take almost as many working-class votes from Labour in some parts of the country this Thursday as they pick from the Conservatives.
In Southampton, the party is particularly concerned about holding on to the council seats up for election in Woolston and Bitterne – traditional strongholds in the city.
And certainly an hour on Bitterne high street suggests this is not expectation management.
Voter after voter talks up Ukip while is hard to find anyone with much enthusiasm for Labour. Even one of the local priests is voting Ukip because, he says, he’s “just fed up with the two major parties”.
This strength of feeling is not just anecdotal. A survey yesterday for a local paper found Ukip support at 21 per cent in Southampton – compared to 25 per cent for Labour and 19 per cent for the Conservatives. At the last general election Ukip polled just 4.3 per cent.
And this threat of defections amongst Labour’s traditional support isn’t just bad news for council elections.
The party is defending a majority of 192 in the parliamentary constituency of Southampton Itchen, with the Tories in second place. Labour also doesn’t have the benefit of incumbency because the current MP, John Denham, will step down in 2015.
In his place, Rowenna Davis is standing for Labour – having given up her journalism job to campaign full time to win the seat. She is disarmingly frank about the Ukip threat. “In white working-class areas the people who are switching to Ukip are our voters,” she says. “In a recent by-election our vote halved and Ukip’s doubled. It is a concern.”
Ms Davis said that in the past Labour had seen voters who complained about immigration as racist - but that was both wrong and dangerous.
“If you take Southampton we had a nine per cent increase in the city's population over six years. Of course that has had an effects on jobs, on housing and public services.
”Immigration is legitimate concern and we've got recognise that and talk about it.“
Ms Davis and Mr Denham have been organising public meetings to specifically discuss immigration - in the hope of convincing their supporters that Labour and not Ukip are better able to address the practical consequences of it.
But they are nuanced arguments about tackling Britain's low wage and low skill economy, increasing the housing stock and investing in public services. They are harder to sell on the doorstep than Nigel Farage's ”shut the door“ solution.
But what about the immigrants themselves? On the same high street as the others are Jurgita and Tarsem Singh – originally from Lithuania and India.
They met in Cyprus and settled in the UK 18 months ago because they felt people would be more accepting of their relationship.
The rise of Ukip worries them. “This new immigrants party just makes us feel uncomfortable,” says Mrs Singh.
“It’s not really racist but it seems like there is a hidden message there. I don’t like it at all.”
And will they be voting?
Yes, they will, they say, “with pride” before adding: “But not for them.”