John Rentoul: Clegg drives his voters away

As Lib Dem allegiance wanes, the remaining few loyalists are bonding with the Conservatives

It is not often that a party leader tells millions of people who have just voted for him that they were wasting their time and should have known it. But that is what Nick Clegg did last week, and what he did at the Liberal Democrat conference last month. He did not put it quite as bluntly as that, but his essential message was unmistakable. He told Andrew Grice, the political editor of The Independent on the opening day of his conference in Liverpool: "The Lib Dems never were and aren't a receptacle for left-wing dissatisfaction with the Labour Party. There is no future for that; there never was."

Well, it was good enough to siphon a million votes from Labour in the 2005 election. And that was enough to take the third party to its highest post-war level of representation in the House of Commons, from which it fell back only slightly in the election this year. In May, the Lib Dems continued to gain from Labour – four seats - while losing ground to the Conservatives – nine seats. So was it wise for Clegg to tell former Labour supporters who had switched to the Lib Dems that they were wrong to see the party "as a sort of left-wing conscience of the Labour Party"?

Perhaps he thought that he could be rude about them because they have already deserted the party. David Cowling, the BBC's top political number-cruncher, has compiled some data on the extent of the collapse in Lib Dem support, and comments: "Defections from the Lib Dems since the May general election can hardly be dismissed as the departure of a few left-wing sectarians." Our ComRes poll today suggests that Clegg has lost fully 10 per cent of the electorate, dropping from 24 per cent in the election to 14 per cent support now.

Instead of trying to win them back, the Liberal Democrat leadership seems to have decided on a policy of confirming its former supporters in the view that they voted for the wrong party. Last week's U-turn on tuition fees seems purposely to shut and lock the door on millions of voters. Not since the poll tax has a policy appeared so deliberately designed to discourage people from voting for the party that devised it.

I say this as a supporter of the policy to which the Lib Dem leadership has now turned: the party has ended up in the right place, but the way in which it has made the change has been utterly disastrous. Partly because the Lib Dems have exposed themselves as opportunists of the worst kind. Clegg and Vince Cable, who was then his deputy, tried in 2008 to end the party's policy of opposing tuition fees. In the party's so-called democratic internal structure (that is, one colonised by vested interests and run by people who have time to go to lots of meetings), they were defeated. You might have thought, then, that when, in the run-up to the election, Clegg, Cable, Danny Alexander, Chris Huhne and David Laws were approached by the pressure group known as the National Union of Students, they might have said to them: "Yes, it is our party policy to abolish tuition fees, but we won't sign your pledge, thank you, because there are many ways of achieving the objectives we all share." Or something. Anything instead of signing the stupid thing and being photographed for the local newspapers.

Admittedly, once you have boxed yourself into an unrealistic position like this there is no easy way out of it. But Cable and Clegg seem to have chosen the worst, again. They could have said that Lord Browne's review had persuaded them that the alternative policy, a graduate tax, was not a good idea, and explained why. Instead, in their emails to party members they said that the public finances were in a worse state than they thought, while Cable said that a graduate tax was only "superficially attractive". So the voters who are disappointed with the party are presumably superficial and unthinking lefties.

Having mislaid and now insulted one voter in 10, the big question for the Liberal Democrats for the next five years is: where will they get more supporters from? It is plainly far too early to try to guess how many seats the Lib Dems might win at the next election if they remain at this sort of level in the opinion polls. So let us try. The Electoral Calculus model run by Martin Baxter would cut the party down to 20 seats. The boundary changes to shrink the House of Commons and to equalise constituencies will make it worse for them; if the Yes campaign wins the referendum to change the voting system, the outcome may be slightly better. But you get the picture: the Lib Dems could be back to the days when the entire parliamentary party could fit in a family saloon.

That is why, in the run-up to the Comprehensive Spending Review, the question of what benefit the Lib Dems gain – as a party rather than as individual ministers – from being in the coalition has been asked with greater intensity.

Clegg's answer on Friday was to pre-empt George Osborne's big day this week by trumpeting £7bn to be spent on the pupil premium for schools with disadvantaged pupils. Except that it turned out to be a cumulative total over three years and the source of the money is as yet unclear. I doubt if that is going to do the trick. But what else do the Lib Dems have? Civil liberties? Being soft on crime? David Cameron and Kenneth Clarke seem to have pre-empted them on those. Green issues? As we report today, Chris Huhne, the Energy and Climate Change Secretary, is finding that they are a lot harder in government than in opposition.

The Liberal Democrats have to get away from the curse of Danny Alexander, Chief Secretary to the Treasury, who last weekend declared of the spending review: "These are our decisions, our reforms, our news ideas, and – yes – our cuts too. Whatever flak we take, in five years' time people will see we did the right thing, for the right reasons." Do you know what? I think that they might. And then gratefully vote Conservative.

Follow John Rentoul on Twitter: twitter.com/JohnRentoul