A veteran political commentator, sadly no longer with us, once counselled me: "Never begin with a number." His theory was that readers were allergic to figures.
I can see him shaking his head, because today I am going to begin with a couple of numbers. Two million eight hundred thousand. One million one hundred thousand. And now I am going to offer you two further, but much smaller numbers. One hundred and seventy thousand. One hundred and ninety thousand.
The first pair of numbers are the estimated peaks of the memberships of the Conservative party and the Labour party, highs that both occurred in the 1950s. The second, much, much lower pair are the memberships currently claimed by the Conservative party and the Labour party. I say "claimed" because all political parties are tempted to massage upwards. And the raw total, even if roughly accurate, does not tell us how many of the members are actually doing anything. The number of energetic participants in political parties is very likely much lower still. We often talk about "activists" when we should really be saying "inactivists".
The political party is dying. Quite literally so. As older members pass away to join the great returning officer in the sky, they are not being replaced by new, young recruits.
This is the context that connects a series of recent, apparently disparate and unrelated events, uproars and arguments. It helps explain both the furore about candidate fixing in the Labour party and David Cameron's persistent troubles managing the Conservative party. It lies behind the regular eruption of donations scandals and feeds into the high levels of discontent about politics and disconnect from Westminster among the public. All these relate to the collapse of party membership.
Even back in the 1950s, belonging to a political party marked you out as slightly odd. More civically engaged than the average citizen, if you want to be nice about it. If you want to be less kind, an obsessive. But at least then, when the combined memberships of Labour and the Tories could be measured in millions and even the old Liberal party could rustle up 250,000 paying supporters, the minority you belonged to was a substantial one. Even if you didn't carry a card yourself, most people probably knew someone who did.
To be a party member these days defines you as very abnormal indeed. One last number, which is 176,632. That is the number of people who, when asked to register their religion in the last census, gave it as Jedi Knight. So more people now follow an eccentric faith based on the worship of Star Wars than are members of the Tory party.
As parties shrivel to a very small hardcore of the ultra-committed, one consequence is that they become less and less representative of the wider population. That makes them even more cut off and even more difficult for leaders to lead. Consider the convulsions that the Conservative party has been through over same-sex marriage. The polls tell us that the average voter is not all that fussed by the issue. On balance, they are positive and they are more likely to support gay marriage the younger they are. The one exception is elderly people. Most are against and many are passionate in their antagonism. David Cameron's basic problem with gay marriage is the average age of a Tory party member. It is now about 74.
As the profile of party members becomes more and more untypical of the country at large, it affects who gets sent to Westminster and not in a good way. The best of luck to anyone who is pro-gay marriage, pro-European and pro-immigration and also happens to be a Tory with ambitions to become an MP. To stand a chance of being selected, they will either have to lie about their views or find a very unusual Conservative association.
Sensible politicians know that elections are won by assembling a broad coalition of voters, most of whom have little or no clan allegiance to any one party. But the shrinkage of parties tends to mean that they are left with only the most tribal of people as their members. This creates the conditions for permanent warfare between leaders, who have to be pragmatic in the pursuit of power, and activists who regard every compromise with reality or the electorate as a betrayal.
Another bad effect is that it is creating opportunities for small groups of people to capture parties. Labour has its current problems with some trade unions – and, to be fair, not just unions – moving in on dwindling constituency parties in order to try to fix candidate selections. It was the low number of members that made Falkirk and other seats tempting targets for Unite. But the Tories and the Lib Dems would be wise to restrain their gloating at Labour's discomfort. Many Conservative and Lib Dem constituency parties have become so shrivelled up that they are ripe for infiltration and takeover by ideological extremists, religious zealots, ethnic cabals or other entryist groups.
The evaporation of the mass membership party has had a further baleful consequence. The parties have become ever more dependent for their financing on big money: union chequebooks in the case of Labour, City chequebooks in the case of the Tories, anyone who walks through the door with a bit of spare change in the case of the impoverished Lib Dems. This is equally true of the supposedly anti-establishment parties. The Scottish Nationalists are very reliant on a few rich donors. Ukip is effectively bankrolled by just one man: Stuart Wheeler, who made his millions from spread betting.
From time to time, usually in the wake of being embarrassed by a favours-for-donations scandal, party leaders talk about funding reform and make noises about rebuilding mass memberships. Sometimes they even make a bit of an effort to try to do it. They find it is difficult, give up and then collapse back into the arms of big money.
This is where Ed Miliband's response to the candidate fixing allegations could have an impact that goes well beyond the current problems of his own party. If he translates some bold words into substantial action, there's just a chance he might even help to bring back some life to all political parties.
I completely agree with his argument that trade union members should no longer be automatically affiliated to the Labour party, but should in future be asked to make a positive decision to opt in before their money is donated to the party. I could hardly not agree having advocated exactly that in this place last week. It is possible – in fact, really very likely – that Labour will take a painful short-term financial hit. But in the longer term, this paves the way for doing politics better. For Labour, this reform has the potential to recast the relationship between the party and millions of citizens. No longer would it be based on deals between the leader and the handful of union bosses who hold the purse strings. Labour would, instead, have to make a huge effort to rebuild itself as a mass membership party financed by the small donations of the many, not big dollops of cash handed out by a few general secretaries. That is the only way Mr Miliband has a chance of making good on his ambitious aspiration to create a party "truly rooted in every community and every walk of life".
His move also bangs the party funding ball back over to David Cameron's side of the net. In the past, the Tories have blocked a clean-up on the grounds that they would not give up trousering large cheques from the City so long as Labour harvested block donations from the unions. Mr Miliband's gambit eliminates that Tory excuse and aligns Labour with the Lib Dems in arguing for a cap on the size of donations, whether they come from unions or hedge funds. Given the resistance of the Tories, a donations limit is unlikely to be enacted before the next election. But it looks increasingly certain that a cap will be implemented the next time we have a non-Tory government. When they can no longer rely on big money, the Conservatives will then also be forced to think about reimagining how they fund themselves.
Some of the shortfall could be found by reforming the state funding of parties. I am told that the cost of the traditional free mailshot given to candidates for elections comes in at £40m a pop. Since most of that mail goes straight in the bin, I am sure the parties could use the cash more imaginatively. While a reordering of already existing state funding is possible, none of the leaders thinks they can sell an increase to the public, certainly not in the current climate. The idea of a bigger state subsidy for parties is almost as unpopular with voters as pay increases for MPs.
So the only way to go will be for all of them to try to reinvent themselves as mass-membership organisations. I don't say it would cure every malady that currently afflicts politics. I can't even tell you whether it is really possible. I am certain it is essential to try. May the force be with you.