Is Labour in serious trouble in the north west seat of Heywood and Middleton, where the party faces a by-election on 9 October?

Until now, all the attention has been on the strong possibility of Ukip winning in Clacton, where the former Conservative Douglas Carswell (pictured below right), who defected to Ukip last month, is widely expected to become the party’s first elected MP.

That, of course, would be hugely embarrassing to David Cameron, and give Ukip a great fillip, with the real possibility of further defections by Tory MPs.

Far more interesting, in my view, is the Lancashire constituency of Heywood and Middleton, whose MP Jim Dobbin died a fortnight ago. It looks ripe for plucking by Ukip.

Local Labour sources certainly think so. “Shadow cabinet members are sh****** themselves about losing,” one Labour figure has told me.

At the last election, Ukip got just 2.6 per cent. Hardly promising. But the BNP got 7.0 per cent. With the collapse of the BNP as a party, you would now expect Ukip to get most of the combined vote, a useful base of 8-9 per cent.

The Conservative vote in 2010 was 27.2 per cent, and the story is that the Tories plan a pretty weak campaign in the hope their voters might help Ukip embarrass Labour, and therefore negate – or more than negate – Ukip’s expected success in Clacton. Not so much a score draw between Tories and Labour, as a score draw away from home.

At least in Clacton the Tories will be able to say it was inevitable they’d lose to a popular former MP who was once of theirs.

The Lib Dems got 22.7 per cent in Heywood and Middleton in 2010, and on the form of recent by-elections will lose about 20 per cent of that this time. Labour expect to pick up most of the lost Lib Dem votes to add to Jim Dobbin’s 40.1 per cent.

I wouldn’t be so confident if I were Labour. Until 2010 the Liberal Democrats were the main party for protest voters; now Ukip are the main place for protest voters, even though the two parties are miles apart on most areas of policy.

The demographics in Heywood and Middleton are good for Ukip, too. A substantial white working-class vote, but unlike nearby Lancashire mill town areas such as Oldham and Rochdale, the ethnic vote is small.

What’s more, the constituency is actually part of the Rochdale borough, which has been beset by child sex abuse scandals which were covered up or ignored by the local Labour and Liberal Democrat establishments. More ammunition for Ukip, as we saw in May’s local elections in Rotherham.

And Ukip has a strong candidate in John Bickley, a former Labour supporter who stood for them in Wythenshawe earlier this year. Bickley claims on his leaflets that he was brought up on a council estate in Middleton. That’s a bit strange, for he claimed in Wythenshawe that he’d been brought up on a council estate there!

The two claims can be reconciled, of course, but it seems terribly lucky that Ukip have a candidate brought up in the only two north west seats to have had by-elections this year!

Despite that, on a brief visit yesterday to Heywood, Ukip had already made an impact with voters. I only spoke to a couple of dozen people, I suppose, but many were unimpressed by Ed Miliband. “A waste of space,” is how one voter described the Labour leader.

I’d want to spend a lot more time in more of the seat before making any predictions, but the ingredients for a shock Ukip win would seem to be there. We won’t really know until people start doing serious polls.

With all its attention on Scotland, then on its conference in Manchester, Labour may have been too distracted to realise what a threat Ukip is in Heywood and Middleton, only 40 minutes by car from the Manchester conference centre.

If I were Nigel Farage (pictured above left), I would take the gamble of doubling my money, take the risk of thinking Clacton is in the bag, and divert a substantial part of Ukip resources to the Lancashire seat. And before that, I’d urge Lord Ashcroft to do a poll in the seat to generate momentum.

And what a win for Ukip it might be, if it came on the same day as winning Clacton – evidence that Ukip was a threat to both Labour and the Tories.

And three weeks later, on 30 October, comes the by-election to elect a new police commissioner in South Yorkshire, following the protracted resignation of Shaun Wright over child sex abuse in Rotherham. Ukip must surely be favourite to win the PCC by-election – yet more embarrassment in Ed Miliband’s home patch, and the home area of several other shadow cabinet members.

Three Ukip by-election victories in one month. And in diverse areas. What would have been unthinkable a few months ago now looks distinctly possible.

It would be an incredible boost to Farage and his colleagues just six months before the general election campaign. And add to Ukip efforts to oblige broadcasters to treat them as the fourth party in British politics.

For the first time, I am starting to think Ukip could end up with a vote next May above 10 per cent and maybe in the teens.

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