TUNBRIDGE Wells MP Archie Norman, a Tory former vice-chairman, has become the first Kent Conservative MP to say publicly that Mr Duncan Smith should go as party leader.

Mr Norman, who recently described the state of the party as “parlous,” said he would not be backing his leader in today’s vote of confidence.

"When you're gone, you're gone. His leadership period is now over," he said. In a statement issued by his office, the former supermarket boss who was once himself tipped as a possible future leader of the party, said: “This has not been a happy three weeks for the Conservative Party.

"Conservatives in Tunbridge Wells and across the country are telling us to get our act together, resolve the leadership issue and get on with the job. That is what we should now do and I very much hope we can all coalesce around one candidate and resolve the matter fast”.

Meanwhile, Ann Widdecombe, the Maidstone and Weals MP and former Tory ex-minister, said she would back Mr Duncan Smith.

"As far as I am concerned, Iain is the duly and properly elected leader of the Conservative Party with a very clear mandate from the constituencies," she said.

Miss Widdecombe, who herself stood as a candidate in the last Tory leadership election, was widely regarded as having destroyed Michael Howard’s chances of the job back in 1997 when she described him as having "something of the night" about him.

A number of other Kent Tory MPs have pledged support for Mr Duncan Smith in his leadership battle. Twenty-five Tory MPs have called for a vote of confidence in Mr Duncan Smith. The whips have confirmed that a vote will take place this afternoon. The result is expected tonight at around 7pm.

Faversham and Mid Kent MP Hugh Robertson, a party whip, said Mr Duncan Smith deserved the support of MPs. He stressed: “I have already urged my colleagues to stop the collective insanity of the past fortnight and to unite behind the leader.

"We have a raft of exciting new policies and we should concentrate on them rather than on self-destructive in-fighting.”

Canterbury MP Julian Brazier said: “I am very sad that it has come to this. I will be supporting Iain, who is presenting the kind of policies the electorate want to see. All the feedback I have had from my local association is that they want him to stay as leader.”

Folkestone and Hythe MP Michael Howard and Ashford's Damian Green have declared their allegiance to Mr Duncan Smith in a joint message of support also signed by shadow cabinet colleagues and potential leadership candidates, Michael Ancram, Oliver Letwin and Theresa May.

The message said: "Iain Duncan Smith is the duly elected leader of our party. He has faced considerable pressure over recent weeks and has done so with remarkable courage and dignity.”

“He has said, and we agree with him, that he has earned the right to lead our party into the next election. He has healed the wounds on Europe.

"He has forged, for the first time in a decade, a radical and coherent programme of reform in the public services. He has once again made the Conservative party the champion of the people and the advocate of choice and opportunity for all.

“Iain has made it clear that he will now seek the support of colleagues in the forthcoming vote of confidence, to draw a line under recent events and to allow him to take these policies forward. We will support him."

Thanet North MP Roger Gale, a party vice-chairman, reiterated his support for Mr Duncan Smith but admitted the rules on leadership elections needed to examined once the dust had settled.

He said: “The fact that there is now going to be a definitive outcome can only be a good thing and we can only move forward from that. I am concerned that whatever the outcome, we preserve the policies that we have developed because they are very good and we have to focus on those.”

It was bizarre that the leadership rules meant that letters asking for a vote of confidence in the leader could rest “on file” indefinitely.

Mr Gale added: “We will have to look at the rules but we cannot change them in the middle of a vote of confidence. Lessons will have to be learned.”

Meanwhile, bookmakers Ladbrokes were offering odds of 6/4 on Michael Howard becoming the Tories' next leader. Fellow Kent MP Ann Widdecombe was being quoted at 50/1.

Mr Howard's nearest rival, David Davis, shadow leader of The Commons, was 7/2, former Prime Minister John Major 500/1 and previous Tory leader William Hague 25/1.

Many Tories in Dover and Deal say they are fed up with the political plotters trying to remove Mr Duncan Smith.

The constituency party in the area want to see an end to the wrangling that is "damaging" the party. In nearby Sandwich members said they are whole-heartedly behind the present leader.

Barry Williams, chairman of the Dover and Deal Conservatives, said: "I can only speak for myself and a few people I have spoken to about it, but we want the issue finished. This does nothing to help us in opposing the government."

Life-long Conservative supporter Patricia Lavers said she agreed with the leader's opinion that his opponents should "put up or shut up."

Mrs Lavers is president of the Sandwich branch of the South Thanet Conservatives and is confident the Opposition leader will retain his job. She said: "I am not impressed by the plotters - they are cowardly and almost treacherous. It is pathetic so few of them are not brave enough to put their heads above the parapet.

"Members of Parliament selected Mr Duncan Smith and the constituencies, like South Thanet, supported them. Why reject someone we have elected? This would be the worst scenario and it would be a waste of time and money to have another election when we should be fighting the Labour government's inadequacies and gaffs."

She added: "I cannot imagine Mr Duncan Smith will not be leading the Conservatives this time next week."