A byelection in the back streets of Brighton and Hove would normally cause no more than a ripple on the national political scene.

Yet the result in Goldsmid ward of the city council could eventually create an electoral tsunami of a kind never seen before.

There are six candidates in the contest and the result has some significance for the council itself which is currently controlled by the Conservatives.

Because one of their former members, Jayne Bennett, has been an independent for some time now, they are tantalisingly short of having an overall majority.

The seat is Tory held and should any other party win, there is a chance that they could later put aside their political differences to force them out of power.

This would be a body blow for the Conservatives, already riven by internal disputes and deeply disappointed that none of the big projects on Brighton seafront shows much sign of progress.

Tories face a problem in that the byelection has been caused by the belated resignation of a councillor who rarely turned up to committee meetings - never a popular move among the electorate.

There is also a UKIP candidate who is bound to take some protest votes away from the Conservatives.

Labour, who have previously fared fairly well in Goldsmid, are handicapped by the national political scene and by opinion polls showing the party at a historic low.

Liberal Democrats have also polled well locally but it is hard to see them being anything but squeezed in this election.

Independent candidate Brian Ralfe has probably stood for election more times than the rest of the contenders put together. He will bring an air of theatre to the proceedings as the promoter of Brighton’s annual gay pantomime.

But it is the fate of Green candidate Alexandra Phillips that could be of great and lasting significance.

Already Greens are a powerful force on the city council with 12 seats. If they win this one, they will be equal with Labour, now the official opposition.

They will also have gained their first seat within Hove, one of the most marginal Parliamentary seats in Britain, currently held by Labour’s Celia Barlow.

Greens could gain a sizeable number of votes in Hove, mainly at the expense of Labour and the Lib Dems. The most likely result of a strong showing would be to help Conservative contender Mike Weatherley regain Hove for his party for the first time since 1997.

Goldsmid is also bang next door to Brighton Pavilion, the seat Greens are targeting for a historic win in the next general election. Indeed around the Seven Dials it is hard to know where Brighton starts and Hove ends.

Last time Keith Taylor, since supplanted as candidate by Caroline Lucas, achieved the best result in Britain for his party.

The seat has been held by David Lepper for Labour since 1997. He is a good constituency MP with a substantial personal vote which will be lost as he is standing down.

Nancy Platts, the new Labour contender, is active and able but she will contest the seat at a bad time for her party.

The seat ought to be a shoe in for the Tories, who held it from its formation in 1950 for almost half a century, often with big majorities.

But Dr David Bull, the charismatic TV medic who has been the Conservative candidate, has been curiously mute for a long time It now transpires that he is standing down to take up another role, leaving his successor precious little time to get established before the election.

This is all good news for another doctor, Caroline Lucas. She is already well known in the area, having been Green MEP for the south east over the last decade.

Caroline Lucas also has a national profile as leader of the Green Party in England and Wales. Radical and articulate, she could hardly be a more formidable candidate.

Greens were greatly encouraged by the results of the Euro elections which showed them well in the lead in the whole of Brighton and Hove. Tories were a distant second while Labour gained only half as many votes.

UKIP, strong elsewhere in the south east, were a minor party in the city while Greens polled three times as many votes as the Lib Dems.

There was a time when the third party was powerful in Pavilion, electing several councillors and coming second in the general election of 1983.

But Greens are gradually replacing them as the party of protest and there is a Lib Dem vote to squeeze at the general election.

Nationally Lib Dems are not faring as well as they should be under the uninspired leadership of Nick Clegg. Indeed the latest opinion poll showed them a percentage point behind the other parties which include the Greens.

At this point I have to point out the case against the Greens. They still seem like a single issue party through their name even though they do have a full manifesto. Some of their policies and a number of candidates seem to be distinctly flaky.

Strong in trendy districts, they still have a long way to go in the suburbs – places like Westdene and Patcham They are absurdly small and when I went to their party conference at Hove Town Hall, there were only a few activists there.

Greens like to portray themselves as different but they suffer from the same diseases of infighting and inflated egos as any other party.

They are reaping the benefits of protest votes now but voters may still feel they would rather support one of the main parties at the general election.

Until recently I have not thought they had much of a chance of victory in Pavilion but I am starting to change my mind now. There is a unique set of circumstances which nearly all favour Dr Lucas.

If Alexandra Phillips wins the Goldsmid byelection later this month, that will be a huge boost for the Greens, reinforcing their claim to be taken really seriously, even in first past the post election.

They could fall as fast as they have risen. I do remember vividly how well they fared in Euro electrons 20 years ago and how that proved to be little more than a political flash in the pan.

But I have a feeling their moment may have arrived in Brighton and that they could also fare well in one or two other seats where they are pressing the old parties hard.

If that occurs and they go on to become an established part of the landscape as in many other countries, Brighton and Hove will be able to claim the Green revolution started there.

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