To save Britain’s EU membership, the party is rallying around John McDonnell

The shadow chancellor's Tory Brexit line has been picked up by some unusual allies.

Britain’s In-Out referendum will won and lost among Labour voters. That’s why Vote Leave are going hard on their illusory pile of money for the NHS, a powerful message for the nine million voters who backed Ed Miliband in 2015.

As I’ve written before, John McDonnell has a catchphrase that he and his team believe will provide the missing incentive that Labour voters need to get them to the polls on 23 June: “Tory Brexit”.

Today the party is going hard on that message, setting out in detail what the “Tory Brexit budget” would look like: additional cuts of £3.5 billion to the Department of Health, and £1.6 billion to the Department of Education in 2019-20 alone.

But the real excitement in Team McDonnell are the politicians they’ve signed up to act as message carriers: Tom Watson, Angela Eagle, Owen Smith and Yvette Cooper.

If McDonnell does one day succeed Jeremy Corbyn as Labour leader, he will have to defeat at least one of Watson, Eagle or Smith to do so, making their involvement and acceptance of the line a major coup. Relations between the shadow BIS and shadow Treasury teams in particular are often frigid, with Team Eagle feeling that McDonnell tends to range too freely into their brief without informing Eagle first, while McDonnell’s aides believe that the shadow BIS team is less enthusiastic about Treasury-driven initiatives that they should be.

But the big coup is Cooper, who some in the Labour leadership believe they may be able to coax back to the frontbench once it becomes apparent that “we’re going nowhere” as one puts it.

There will be some positivity to offset the largely negative “Tory Brexit” message. A significant speech from McDonnell is planned next week, while Chuka Umunna and Emma Reynolds, who have been ever-presents on the referendum campaign trail, will continue to make the positive case. “Tom Watson will play the bad cop and John will play the good cop”, explains one staffer.

Labour are increasingly nervous about the referendum, and the party is betting big on the “Tory Brexit” line to get its voters to the polls. But their problem – and the wider In campaign – remains the same: there is no positive offer in Cameron’s renegotiation to get Labour voters to the polls. The hope for McDonnell is that Labour’s adoption of his line hasn’t come too late.