THE line between bravery and foolhardiness can be extremely narrow and it might only be on May 8, 2015 that we find out which side Ed Miliband has fallen on after his Clause 4 moment near Labour's birthplace in London.

The party leader said he wanted to "build a different kind of politics" after the bruising row over alleged vote-rigging in Falkirk and intends to redraw the party's relationship with the trade unions by getting individual members to choose to opt in to becoming affiliated members rather than leave it up to the union machinery to automatically sign them up.

During his post-speech Q&A yesterday, Mr Miliband admitted what, to most people will seem a dry, technical move, would have "massive financial implications" for his party.

The affiliated fee is worth more than £8 million a year to Labour HQ with some three million trade unionists signed up automatically.

The Labour leader was adamant that a) he was absolutely determined to see the change go through and b) he wanted it to happen before the next election.

Given that increasingly the outcome of elections is dependent on how much money a party can spend and given Mr Miliband recognises Labour could lose millions of pounds of income, he might conceivably have just lost the next election.

In 2010 the Conservatives spent more than double their main opponents, laying out £17m compared to Labour's comparatively modest £8m.

If Mr Miliband gets his planned funding change through in the next few months and his party loses, potentially, millions of pounds as a result of the numbers of affiliated members paying the annual fee falling away, where is Labour going to get its campaign money from?

A Shadow Cabinet member seemed remarkably sanguine when I broached the idea. He pointed out that the problem with funding comes in the two to three years after an election; the two years prior to the next usually pose no problem as people are willing to be part of, what they hope, will be a successful campaign.

But, of course, this implies Labour, having lost a whole heap of money by scrapping the old system of automatic affiliated fees, will have to turn to wealthy individuals to fill the gap.

Not, I suspect, what Mr Miliband had in mind when he spoke about opening up politics to the ordinary working classes.