Yesterday was the feast day of St Jude, the patron saint of impossible causes. There are some who say that leading the Conservative Party is an impossible cause. I do not believe that. It is a great honour to be my party’s leader, and to be the first Conservative leader to have been elected by the party’s grass roots. I have no intention of walking away from my duty to my party. It is my duty to protect the achievements of my leadership. It is my duty to address the shortcomings of my leadership. And it is my duty to warn my party of the grave consequences of a leadership election.

My first duty is to protect the achievements of the past two years. They are achievements that belong to the whole of my frontbench team. When I became leader, in the shadow of the tragedy of September 11, we lacked a policy programme, a political strategy and a campaign plan. We now have them.

We have caught up with Labour in the polls and have re-established ourselves as the largest party in local government. We are united on Europe for the first time in a generation. And perhaps most importantly of all, we have policies on pensions, law and order and the public services that are popular, genuinely Conservative and which will make a real difference to people’s lives.

Halfway through the Parliament, we are halfway to Downing Street — and I know that the road ahead is easier than the road we have travelled. Now is not the time to turn back. Over recent days I have held many conversations with colleagues. I have listened and have heard what they are saying about my leadership. I have a deeper understanding of the shortcomings of the past two years, and of what needs to be done to address them. That is my second duty: to develop as a leader.

No book has been written on how to be Leader of the Opposition, and I have made mistakes. Not all of my staff appointments have been successful, but I have now built a team of senior advisers that can take us to the next election.

If the first half of my leadership was about policy development, the second half will primarily be about campaigning. With my chairman, I plan to reshape Central Office to become a real election-winning machine once again. In the parliamentary party, I have worked with people from all wings of our party, including many with different views on Europe. I want to make that a bigger feature in the future. This party needs the experience of some of the most senior figures from our time in government.

My third duty is to be honest with the Conservative Party about the consequences of a leadership contest at this time. A time when so many people are hurting in this country. A time when parents despair of finding a decent school for their children. A time when young people should be looking forward to university, but are more afraid of falling into debt. A time when older people should be looking forward to retirement, but wonder if their pensions will be enough. A time when the elderly despair of ever seeing a police officer on their street. A time when everyone is sick of paying so much tax for so little in return. In short, this is no time for the insulting irrelevance of a leadership contest.

A beauty parade of politicians would look pretty ugly to a nation desperate for an alternative to a failing Government. Do not imagine that the British people will fail to notice if we turn our backs on their concerns for the rest of the year. Do not think that they will not hear the deafening silence of an official Opposition too busy to concern itself with what really matters to ordinary people. And do not kid yourself that they will ignore such a flawed sense of priorities.

There is not a single polling organisation in the country that has identified one of my parliamentary colleagues who would improve this party’s opinion poll rating. Three months’ infighting would seriously erode our support in the country. In two years I have taken the party from a hopeless second best in the polls to a position in which Labour and the Conservatives are neck and neck. What is the point of falling behind once more under another leader?

Whatever happens in today’s vote, I enjoy the personal security of a wonderful family. Today, my overriding concern is for this party and for the hard-working, law-abiding people that we have always stood for. They are desperate for an alternative to this failing Government. They are desperate for a Conservative government that will free them from the unfair burdens that Labour has loaded on their backs. Tax. Regulation. Congestion. Crime. Every day that Labour has been in power, life has become tougher for the people who make this country what it is. They will be the losers if this party chooses the path of a self-indulgent leadership contest. They will be the losers if we do not exploit this moment of maximum vulnerability for Labour.

On a grey, cold, wet day in February last year, I visited the people of the Easterhouse estate in Glasgow. I dedicated my leadership to making this country theirs as much as it is ours. I want to build a Conservative Party that can solve the giant problems that dominate their lives, but which increasingly threaten everybody.

When the British people wake up on Thursday morning, what kind of Conservative Party will they see? One ready to finish the task I have begun, or one ready to plunge into the unknown? A party that cares about Britain, or a party that cares only about itself?

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