Why today's by-election in Clacton matters so much

A victory for Ukip in the early hours of tomorrow will send a clear message to both David Cameron and Ed Miliband that traditional party loyalties can be broken down by the right candidate with the right message.

If Mr Carswell wins and Mark Reckless – the Kent Conservative MP who also defected to Ukip – holds his seat in Rochester, they will provide succour to other potential Eurosceptic Tories who could well follow in their footsteps as the next election approaches.

Others are contemplating the move, and could well jump ship if the omens look good. Not only this but Ukip is at a crucial juncture in its attempt to move from political pressure group to a genuine political force.

There will be a sense of momentum. The party and its candidates will be taken more seriously by the media. Ukip can make a more convincing argument for why Nigel Farage should be allowed to take part in any televised debates ahead of the next election.

Not only this – if Mr Carswell (and others) can hold on to their seats in 2015, then they will be entitled to state support in short money given to political parties with Westminster representation. This will allow Ukip to employ permanent staff at taxpayers’ expense, supplementing the money the party receives from Europe. It can also make a stronger argument for their own representation in the House of Lords.

Besides defections, the party is adopting a strategy used to great effect by the Liberal Democrats in the 1990s, of being the insurgent challenger – winning by-elections and then using those as a base on which to build support at a general election. Clacton may only be one seat – but its symbolic and practical significance goes way beyond its size.

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