Move over Barbie Bus, this weekend it is the Purple Godiva – my dark metallic purple V8 Jaguar Sovereign with Ukip yellow 'go faster' battle stripes – that is hitting the Election campaign trail.

Still, after Labour Deputy Leader Harriet Harman's lipstick-pink 'Woman to Woman' minibus so spectacularly backfired on its launch last week, I thought it would be wise to consult my wife Laura about my own campaign slogan before the Jag was delivered to a Wolverhampton firm for its Ukip makeover.

'Anything but Man to Man, Vote for Cash,' she replied sharply.

Ukip's head of policy, Suzanne Evans, suggested 'North Warwickshire needs Cash' – in reference to the constituency I'll be fighting for Ukip in May.

'Well, you don't disobey the boss, especially not a woman, so I made up stripes with her suggestion, along with Ukip-isms such as 'A Return to Common Sense'.

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Electioneering: William cash writes: 'Move over Barbie Bus, this weekend it is the Purple Godiva – my dark metallic purple V8 Jaguar Sovereign with Ukip yellow 'go faster' battle stripes'

The slogans are printed on magnetic strips and cost about £25 each, although apparently you have to be careful not to drive your campaign car too fast, lest they fly off and injure would-be voters.

This item of campaign wisdom came from my mother, neighbour (and long-serving political wife of Conservative MP Sir Bill Cash) who came into my kitchen within an hour of my new purple Jaguar being parked visibly in our shared courtyard. 'What on earth is that?' she exclaimed. Well, it proves the car is eye-catching…

And yes, the postman will find it bizarre to pull up next to two campaign battle wagons, both saying 'Vote for Cash' – only decked out in different political colours.

The only other piece of advice my mother gave me was to take the slogans off when not in the constituency I'll be fighting. 'Voters get confused about names. That's why politicians use magnets, so they can take them off easily.'

Then we walked outside and inspected my new vehicle. Despite being built in 1998, the car is was what the trade refer to as 'immaculate'. The classic car ad that caught my eye ran: 'Very rare purple metallic with cream leather. Top-of-the-range model with all the usual refinements expected. Needs to be seen and driven to appreciate the condition.'

As my mother admired the sleek Jaguar lines and finest English hide upholstery, did I detect I tinge of campaign car jealously?

Back-fired: Will Cash says the pink bus Deputy Labour Leader Hariet Harman used in a bid to get women voting 'spectacularly backfired' The search had not been easy. I nearly bought a silver 1987 Jaguar Sovereign from a dealer in the New Forest. It was advertised for just £950, which made me slightly nervous. When I got inside, I understood why. The polished mahogany dashboard had half curled off, the steering wheel was off-kilter and, the indicators didn't work. Such an Arthur Daley-style rust-heap wasn't going to fit the bill.

Finally, I tracked this one down to Blackpool, being sold by a former hotel owner. He had decided that parking his 'Turkish Delight' in central Blackpool was asking for trouble. 'There are pubs which open at 9am and so many people are just layabouts,' he said as we cruised along the seafront where many shops and bars were boarded up. He wanted £2,450 but we settled at £2,075. The Jag is not a rich man's car.

The car is now named after Lady Godiva, who rode through Coventry naked to get her husband to abolish high taxes in the 11th Century.

As my party's tourism spokesman, I'll be using the Jag to tour the countryside and coastal regions of Britain, to promote more visits to our hidden gems.

But as much as I am opposed to higher taxes, I cannot promise my wife will be inside naked.