The Staggers 1 June 2016 How Jeremy Corbyn will use workers rights to keep Britain in the European Union The Labour leader will "go heavy" on workers' rights in a speech on the European debate. Photo: Getty Sign UpGet the New Statesman's Morning Call email. Sign-up How do you get six million Labour voters to keep a Conservative Prime Minister in their job? That’s the challenge that Britain Stronger In Europe and the Labour leadership are grappling with as the referendum campaign enters its final phase. The party leadership is betting big on ‘good cop, bad cop’ approach: on the one hand, a positive message about Europe and what it can do, delivered from the left by the likes of Yanis Varoufakis, shadow Europe minister Pat Glass and from the centre-left by committed Europhiles like Emma Reynolds and Chuka Umunna. But the big gun is the fear of a “Tory Brexit”, a Labour spin on the messages that the Remain campaign’s pollsters believe are most effective: warning about the risks of a leap in the dark, but conceding that the European Union is an imperfect institution. Yes, you can be concerned about Eurozone-enforced austerity or limits on the abilities of a Labour government to renationalise certain industries – but a Leave vote would be negotiated by a Conservative government and very probably one to the right of David Cameron. Labour insiders say that the message is paying dividends in getting their voters to the polls (postal votes are now being sent off and the party is trying to make sure as many of its voters with postal votes are casting them for Remain). The fear of a Conservative-negotiated Brexit is a strong incentive for Labour voters who are instinctively sympathetic to a Remain vote to get out and vote for one. For those Labour voters who are more sceptical towards the European project, the reminder that the terms of exit would be set by the Tories helps to bring them round to the idea that the status quo is better, at least for now. So far, John McDonnell is the most senior Labour politician to give that argument an airing, but it will receive a boost tomorrow morning with a speech by Jeremy Corbyn in which he will go hard on workers’ rights, talking up how many have been delivered through the European Union and how a Brexit negotiated by a Conservative government would put those rights through the shredder. The hope, too, is advertising the Tory credentials of the Out campaign will weaken Vote Leave’s big arguments about getting more money into the NHS and cutting down on unskilled immigration. Stronger In’s polls – and the public focus groups published by the Eurosceptic peer Lord Ashcroft – find that the austerity narrative works against Vote Leave’s “more money for the NHS” angle. “People don’t believe a Brexit vote would get us £350m more [for the NHS] even if they believe the figure,” one staffer says, “They say: oh, it would go on tax cuts or on paying down the debt. Then when you remind them that Vote Leave’s big players have all suggested selling bits of the NHS, it’s punching a bruise.” Will it work? As I’ve written before, Corbyn is the politician best-placed to win Labour voters over and to get them to the ballot box. Labour will hope that wedding their biggest gun with their best message will do the trick on 23 June. › The new X Factor line-up of old faces proves the show is beyond even nostalgia Stephen Bush is political editor of the New Statesman. His daily briefing, Morning Call, provides a quick and essential guide to domestic and global politics. He also co-hosts the New Statesman podcast. Subscribe For more great writing from our award-winning journalists subscribe for just £1 per month!