If Ukip comes back, it won’t be good news for the Tories – or Labour At the last election, the Conservatives didn’t have a clue but they did have an insurance policy: people who voted […]

At the last election, the Conservatives didn’t have a clue but they did have an insurance policy: people who voted for Ukip in 2015. Even as Theresa May gaffed her way around the country, alienating Remain voters, animal lovers, the young, the old and almost anyone else you might care to name, she survived because she was able to combine the core Tory vote with the support of the United Kingdom’s most committed Leave voters.

Labour support hit 40 per cent of the vote – usually enough to guarantee not just victory but landslide victory – but they had to be content with a close second in terms of votes and a distant one in terms of seats.

Shortly after the election, Tory strategists comforted themselves that, despite a disastrous election campaign, they had seen “peak Corbyn”. Labour’s leader had fought a brilliant campaign, with popular policies and pretty of celebrity endorsements, and still lost.

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Peak Corbyn

The peak Corbyn thesis may well be right: it could be that in an increasingly polarised country, 40 per cent is the upper limit for what Labour can realistically expect to get at a general election, particularly with its current leader. But the Conservative problem is that Labour don’t necessarily have to gain votes to gain seats – the crucial word in our first past the post electoral system is “first”.

If Labour get 40 per cent next time but the Conservatives get 35, 34, or 33 per cent, then suddenly peak Corbyn delivers not electoral defeat but victory – perhaps even a narrow parliamentary majority.

It could be that in a polarised country, 40 per cent is the upper limit for what Labour can expect to get at a general election

And the Conservatives have a big problem, because Ukip voters didn’t stick with Theresa May out of a particular affection for the Prime Minister but because they trusted her to deliver on the terms of Britain’s Brexit vote.

The difficulty for May is that delivering Britain’s Brexit vote is a bit like your friends asking you to deliver a takeaway, which could mean anything from any corner of the world. Whatever deal she brings back – if she can even bring one back at all – will disappoint some people, particularly former Ukip voters, who have sky high expectations for Brexit.

Of course, very few of us will have the time to look at the detail of May’s deal – instead, what most people will reach a conclusion based on what a handful of trusted sources tell us. For former Ukip voters, “trusted sources” means two people in particular: Boris Johnson and the party’s former leader Nigel Farage. Both have no political or tactical interest in praising May’s deal.

‘Purple firewall’

Small wonder that, as a result, Ukip have started to inch up in the polls, putting Labour into the lead even though the party has gained no additional support itself. Senior aides to Corbyn believe that the past week has breached May’s “purple firewall” – and that they will be the beneficiaries.

Are they right? It’s true that the Brexit that the Conservatives have promised will never materialise. In international trade, as in life, the trade-off you make is between freedom of choice and economic security. The more freedom you have, the less trade. That isn’t necessarily a bad thing – there is more to life than the bottom line – but the big lie being sold to voters is that you can have both. When that fiction is exposed, it seems likely that people will blame the government, and not unreasonably.

After the election, Tory strategists comforted themselves that they had seen “peak Corbyn”

Team Corbyn also think that, as Ukip voters align more closely to Labour on economic issues than they do to the Conservatives, they can peel off some votes directly.

On paper, it looks like a clever plan to get their man into Downing Street. But in the real world, it’s fraught with risk, for three reasons. Firstly, since the referendum result, Ukip have moved even further to the right and are a considerably more dangerous proposition than they were before. Secondly, by the time of the next election, Brexit will still be unresolved: and Labour will be left with the unappealing task of implementing the irreconcilable promises of Vote Leave.

But the third problem is that not so long ago Ed Miliband’s closest aides believed that Ukip 1.0 would ease his path to Downing Street. Come the election, it turned out that Ukip were as much a threat to Labour as to the Conservatives.

When Ukip were polling at seven to eight per cent – as they are at the moment – that was true. When, gifted coverage by the big broadcasters, they grew to 15 per cent, they did damage to Labour. Ukip 2.0 may end up going on a similar journey.

Stephen Bush is special correspondent at the New Statesman

@stephenkb