Will Jeremy Corbyn manage to persuade the constituents of Calder Valley to swing red?

• Video report by ITV News National Editor Allegra Stratton

As Jeremy Corbyn launches Labour’s election bid in Battersea we thought we would head the other way. 250 miles the other way: to West Yorkshire and the ultra-marginal seat of the Calder Valley.

The election result in London has been called ‘the jewel in Labour’s crown in 2017’… and that’s true: it delivered the party’s biggest regional swing and their largest vote share in 25 years.

But the thing about crowns is that they usually have some other jewels, or at least something else to say for themselves: so what about elsewhere in the country?

Like the Calder Valley in West Yorkshire.

It’s Labour’s 14th target seat and the Tories currently hold it by only 609 votes. It should fall nicely into Labour’s lap and be one of the 64 extra seats Labour need to win for a majority.

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West Yorkshire has become something of a battleground: Theresa May launched her 2017 manifesto down the road in Halifax; when Boris Johnson launched his policing announcement in September – that terrible fail of political theatre where the trainee police officer fainted behind him - he did so in Wakefield.

Both of these constituencies are currently held by Remain supporting Labour MPs Holly Lynch and Mary Creagh respectively and are key Tory targets.

The neighbouring Calder Valley is somewhere the party will be looking to hold on to.

Holding on, and targeting, in this region will require a similar push by the Tory party machine: to mobilise Leave voters; neutralise any suggestion the Conservatives are out of touch posh boys and convince they are the guardians of public services.

But can Labour advance here? Last election they needed a swing of 4.2% to win in Calder Valley and they got 3.6%.

Labour’s better than expected election result was partially attributed to Jeremy Corbyn’s performance during the 2017 campaign.

We’ll be looking to find out if he went down well here and whether – now that this secret weapon is no longer secret, he is still a weapon: can he help them squeeze out the extra 0.6% swing to turn Calder Valley red? Does allotment-tending, sandal-wearing, north Londoner Jeremy Corbyn connect?

And what will be the issues? We know Labour don’t really want to talk about Brexit. Instead they want to talk about austerity.

This morning Jeremy Corbyn’s speech about the economy being rigged by vested interests and a powerful elite like Rupert Murdoch, Sports Direct boss Mike Ashley and the like. Will this get their (clean green) juices flowing in Hebden Bridge - the spiritual heart of Calder Valley?

It is the location for one of my favourite ever TV programmes - Happy Valley - but anyone who has binged watched that knows there is more to the area than vegan cafes and golden stone terraced streets clinging to the hillside above the town.

How well will Jeremy Corbyn’s version of socialism go down in a place like the Calder Valley with a low level of unemployment – 4.1%, only slightly above the national average of 3.8%; high level of home ownership and a heavy dose of Yorkshire spade is a spadism?

I’ll update you after our day’s reporting. Wish me luck making a political TV election package on Halloween that uses ‘trick or treat’ gags sparingly.