Thursday is polling day for the Wythenshawe and Sale East by-election, and for many of our party activists who have been pounding the streets it can’t come soon enough.

Normally we’d hope for a longer stretch between the calling of the by-election and the holding of the vote – particularly given the huge hurdle all contenders have to face with the postal vote essentially stitching up the result barely half way through the campaign. We even ran an advert in the local newspaper telling people not to trust postal votes to party activists offering to “help” them. But during this campaign, the level of abuse that we have been subjected to by BNP and Labour activists has been so high that the police had to be called on four separate occasions.

There have been two cases of criminal damage, with the vitriolic phrases “f**k off scum” and “Leave Sale Nazi c**ts” spray-painted on our premises. The generator, used to provide power in the party shop at the beginning of the campaign, was stolen by opponents. Groups of activists even ran into the Ukip campaign shop to steal bundles of our campaign literature.

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But what I find truly horrifying is the extent to which those on the left think that they “own” working-class votes. With two-party politics prevalent for so long in this country, there are great swathes of the political establishment that seem genuinely to believe they don’t need to represent their core constituencies any more, that their success is guaranteed, and that they barely have to lift a finger campaigning. But recent by-elections in the north of England have shown that this is no longer the case.

Only this week, Douglas Alexander has announced that an “anti-Ukip” unit will be established within the Labour Party structure, dedicated to attacking us and to protecting the vote that they are (of course) entitled to from straying to pastures new. The realisation that we are taking votes from their traditional heartlands has finally reached Labour HQ in London.

But I wonder what Mr Alexander would make of the behaviour of the red rosette-wearing activists in Sale screaming into the face of Ukip-supporting pensioners, calling them “Nazi racist scum”? And will he back the view of his fellow party members who warned Ukip supporters who have boards up in their garden that they must be taken down because, “They’re our houses, they’re council houses”.

Does Labour really think that anyone who receives housing assistance from their local authority has to vote for them? That they wouldn’t dream of voting for another party even though Labour now admits that they have let people down with their policy of uncontrolled migration?

The BNP has also been involved in nasty tactics in Wythenshawe, again upset because they believe they have some kind of “ownership” over certain votes. In their opinion, anyone disaffected and on the left should be passing their vote to the BNP. But many people don’t want to support an openly racist party and while they may have reluctantly done so before while “holding their noses”, unaware that there was another party to vote for which was anti-Establishment, they are now relieved to find a palatable and decent party that is truly reflecting their concerns.

Our candidate was surrounded by BNP activists when he was out campaigning and I had to beg to use the fire escape of a coffee shop after a crowd with a megaphone attempted to block me in. This is a situation which political parties should be ashamed of. People fought and died for our liberty and democracy and we must not ever allow politics to be tainted by such poor and in some cases criminal behaviour, where free and fair campaigning is distorted by threats of violence and damage.

It is something that particularly emanates from the left. Far from being the party of the people, the party of the workers, the party of the ordinary men and women of the UK, the left wing risks – particularly at grassroots levels – becoming a movement that uses the sort of bullying it feigns to oppose in big business and among the elite.

When it comes to drugs policy, I agree with Nick

Last week, Nick Clegg returned from a trip to South America. Goodness knows what he smoked out there, because he actually made a couple of smart points. First, the so-called War on Drugs isn’t working. Second, we should appoint a royal commission to look into the alternatives.

The fact is our current approach to drugs is neither practical nor effective. I strongly believe in promoting individual freedom – but I also strongly believe in reducing the public harm caused by drugs. As a parent as much as a politician, I say we have to accept that current policy has not achieved the reductions in crime or consumption that we’d hoped for. I know he slagged me off in this newspaper yesterday, but on this one I agree with Nick.