So fractious have the negotiations over the 2015-16 Spending Review been that, at various points, some ministers have urged George Osborne not to hold one at all. But Osborne, who has scheduled the review for 26 June, was never likely to take their advice. For the Chancellor, the event is critical to the Conservatives' strategy for the 2015 general election. By setting spending limits for the first year after the election in advance, he will establish "the baseline " and challenge Labour to match it. Should it fail to do so, punishment will be swift. In a rerun of the Conservatives' 1992 campaign, Osborne will accuse Labour of planning to hit Middle England with a "tax bombshell" to fund higher spending.
Whether or not pledge to match the coalition's spending plans, as Labour did with the Tories' in 1997, is the biggest political decision Ed Miliband and Ed Balls will take before the general election. If they accept Osborne’s baseline, the left and the trade unions will accuse them of embracing "Tory cuts" (something that, in the words of one Labour MP, “would make the row over the public-sector pay freeze look like a tea party"). If they reject it, the Chancellor will accuse them of planning billions in additional borrowing or tax rises.
Having abandoned hope of meeting their original deficit-reduction targets, the Tories believe another election fought over austerity could yet favour them. In 2015, their pitch will be, “Yes, it’s taking longer than we thought. But who do you trust to finish the job – the government, or the ones who got us into this mess?”
A pledge by Balls to match Osborne’s spending plans would be an efficient means of closing down this line of attack. For this reason, it is an option that the shadow chancellor’s team notably refuses to rule out. As chief economic adviser to Gordon Brown, Balls helped mastermind the original 1997 pledge and has already declared that his "starting point" is that Labour will "have to keep all these cuts", a step towards accepting Osborne’s baseline. When Harriet Harman told the Spectator  last September that Labour would not match the Tories’ spending plans and abandon its “fundamental economic critique” of the coalition, she was forced to issue a retraction .
A promise to stick to the Tories’ baseline would not entail supporting all of the cuts proposed by Osborne; rather, Labour will need to replace any cuts that it rejects with tax rises or cuts of equivalent value. While acknowledging that it cannot avoid austerity, Labour would vow to distribute the pain more fairly, ensuring that the richest bear a greater burden. The party will likely pledge to reintroduce the 50p top rate of income tax and adopt some version of a "mansion tax" (a proposal but not yet a manifesto commitment).
Against this, however, is the fact that signing up to the Conservatives' plans, a trick straight out of the New Labour playbook, would run entirely counter to the post-Blairite spirit of Miliband's leadership. Embracing Tory levels of austerity would also deny the economy the stimulus it so desperately needs. For these reasons, senior MPs, most notably Peter Hain , and groups such as the Fabian Society  have already urged Labour to reject this course of action.
Whichever path Balls and Miliband choose, don't expect an answer this year - or next. As today's Guardian reports , the party is likely to wait until just a few months before the general election before announcing its decision (as Blair and Brown did in 1997). This is smart policy as well as smart politics. With the economy and the public finances so volatile (borrowing has been revised up by £245bn since 2010 and growth has been around 6 per cent lower than forecast), Labour can reasonably argue that it is in no position to make a decision more than two years out from the election. Balls and Miliband have learned from the mistakes of the Tories, who pledged to match Labour's spending plans in 2007 only to abandon this pledge after the crash in 2008.
The Conservatives would like nothing more than for attention to be diverted away from their economic failure and onto Labour's plans. It is an opportunity that Balls and Miliband will rightly deny them. But as political pressure (from right and left) grows on Labour to declare its intentions, the next few months will provide the greatest test of party discipline yet.