WITH a General Election expected next May, when should a political party change its leader?

Liberal Democrat leader Charles Kennedy, with his party buoyant, is unassailable, and Tony Blair - despite the bloody mess in Iraq, the loss of trust, his personal health and family worries - looks safe in his job until at least a year after polling day.

The casual observer might think that Roger Knapman, leader of the UK Independence Party, should also be able to sleep soundly at night. Only a political anorak would recognise his name, but this year the country has come to recognise his party. The number of Ukip MEPs quadrupled in the summer and Ukip came commendably third in last week's Hartlepool by-election.

Yesterday, though, Robert Kilroy Silk announced he wanted to oust Mr Knapman and take over as Ukip leader.

It is true that a sizeable slice of Ukip's success has been because of Mr Kilroy Silk's magnetic celebrity status.

But there is something of the demagogue about Mr Kilroy Silk. He might genuinely want to pull Britain out of Europe, but he sounds as if his main motivation is to get his ego out onto the largest platform possible.

With real electoral success a distinct possibility for Ukip in the Spring, the last thing this nascent party wants to do is become a one-man, rabble-rousing, show.

So the only leader in a precarious position should be the Conservatives' Michael Howard.

Mr Howard, understandably, is making much of Mr Blair's decision to step down in five years' time. Mr Howard is calling him "a lame duck"; but then Mr Howard himself looks rather like a cooked goose.

The Tories have made no progress since he became leader last November. In fact, with Ukip's rise and Mr Howard's recent reshuffle, they have gone backwards.

Mr Howard has done little to enthuse either his party or the populace, and the Conservatives have presented extremely few policies or ideas for the public to consider before the election. Perhaps this week's conference will change that.

But it was last year's conference that saw off Iain Duncan Smith, Mr Howard's predecessor.

Even the most lacklustre of conferences, though, won't see off Mr Howard. Going for a fourth leader in four years would smack not just of desperation but of panic, and installing him with only a couple of months to marshal his thoughts before the campaign begins would be suicidal.

However desperate the Tories' position, they wouldn't do that. Surely?