The Liberal Democrats are in deep trouble. In private they are very, very worried indeed. It is not just their poor poll position that is gnawing away in their stomach. It’s that they know, in their hearts, that they are stuck; not just with the blandest leader since their foundation, but with his approach that they neither understand nor share.

Nick Clegg’s leadership has utterly failed to generate the excitement, the new politics or the new policies that he promised. And there’s no sign that it’s going to. Their poll position is dire. And against the fall in our support, they should be riding high. So what’s the problem?

First, they have lost their USP, that they are different. Not surprising given the personality of their leader. It’s difficult to recall any statement, speech or activity from Nick Clegg. If you can, you are an anorak. Partly, it is due to the attempts by David Cameron to portray the Conservatives as a centrist party which squeezes the Liberal Democrat identity. But mainly it’s because in their failure to define themselves, they are losing the supporters, anti-Labour and anti-Tory, who could give them the boost they need. They have thrown away their brand.

Here’s why. There is no such thing as a Liberal Democrat voter. Or at least only about 2-4 per cent of the public describe themselves as Liberal Democrats and vote that way come what may. Where they do well, it’s by galvanising the anti-incumbent and anti-politics vote. Paddy Ashdown understood this. He attempted not just to build his party but to spread an understanding and an identity amongst the public to build a core vote. As much as he railed against tribal politics, he knew he needed his own tribe. As Nick Clegg tries to reposition them, he takes away this more strategic approach. In fact, the evidence shows that where they have achieved success, in isolated local council elections, it’s because they benefit more from the anti-factor and increasingly less from their own pitch. The numbers who see themselves as Liberal Democrats are shrinking.

This presents them with a paradox which is puzzling them. They see strong organisation in many areas yet their support diminishing. Contained within this is good news for Labour. The Liberal Democrats and the Liberals before them are the most anti politics of all the political parties. The oft polished charge that they are all things to all people IS true – yet despite this they are falling behind. Why? Not just because they are not a credible party of government. Those voters who want a credible party of government dismiss them because of this – but even those who don’t, the anti-politics, “you’re all the same”, non voting cynics – they don’t want them either. Why? Because they haven’t got a clue who they are or what they stand for. Look at the by-election and local election results.

Commentators say this is simply a function of Nick Clegg being a pale imitation of David Cameron. In fact the problem he faces is deeper. His leadership campaign and the direction he is now trying to pursue were based on a reactionary, small government, lower taxes approach which fails to address the very concerns he himself highlights as the public’s concerns; prices, crime and public services. The public want the state to be on their side in these battles.

Neither can it be blamed on the media. Of course he doesn’t get the airtime or column inches of Cameron. But that’s not because he’s the third party leader (Charles Kennedy was better known than most cabinet members), it’s because he doesn’t say anything.

Their problem is deepened by the confusing messages that local Liberal Democrats send out. They contradict the national message, for example they call for CCTV to fight crime locally but at a national level they attack CCTV as an abuse of liberty. The result is a mish-mash. In essence they are a flotilla, part of the same fleet, but sailing in different directions. They need to be a battleship.

In fact it’s even worse than that. Nick Clegg, unlike his predecessors, doesn’t understand why he is a Liberal. Of course, he’ll talk about civil liberties and the state, cliché on about bottom up politics and when he’s in real trouble; he’ll quote John Stuart Mill. But he doesn’t live and breathe it. He doesn’t get the beating heart of British Liberals, he is not of it, nor converted to it and they know it. They have chosen a manager not a leader.