Iain Duncan Smith warned his growing band of Tory critics today that he will not be driven out of his job without a fight that would divide the party and damage its chances of winning power.
He told his party's annual conference in Blackpool: "Get on board or get out of our way."
"I say to everyone here today, you either want my mission or you want Tony Blair. There is no third way," he declared.
After a disastrous conference, at which policy announcements have been overshadowed by speculation that Mr Duncan Smith will face a leadership challenge, his keynote speech will play a crucial role in determining whether he survives as party leader.
The Conservative leader received a warm reception and speaking not from a lectern but pacing the stage, his speech was frequently punctuated by enthusiastic standing ovations.
But his prospects worsened as some constituency activists called his leadership into question. Their intervention was important because the Tory leader is elected by the party's members, and some MPs have been waiting for a signal from the grass roots before moving against him.
One MP told The Independent that he would definitely write on Monday to Sir Michael Spicer, chairman of the 1922 committee, calling for a vote of confidence in the party leader. Another backbencher said: "We have made great strides on policy but how can you articulate policy with a leader who is inarticulate?"
In another sign of the gloom in the Tory leadership, a party whip admitted: "There is a kind of fatalism around. You know there is trouble when there is no one talking to the whips."
Mr Duncan Smith raised the stakes today, making clear that the self-styled "quiet man" of British politics will not go quietly. "To those who doubt and to those who deliberate, I say this: don't work for Tony Blair, get on board or get out of our way. For we have got work to do.
"And to the Prime Minister I say this - the quiet man is here to stay and he's turning up the volume," he told the conference.
The Conservative leader promised: "We will always be a lower tax Government than Labour. And yes - we plan to cut taxes."
He repeated pledges to introduce a "Better Schools Passport" to help parents get their children into a school of their choice and a "Patient's Passport" giving people the chance to have private treatment partially funded by the NHS.
Mr Duncan Smith told representatives he would lead a campaign nationwide for a referendum on the proposed EU constitutional treaty saying: "I promise you - I will fight, fight and fight again to save the country that I love."
Mr Duncan Smith will repel any move by Tory grandees, dubbed "the men in grey suits", to persuade him to stand down voluntarily to avoid the humiliation of his MPs triggering a vote of confidence.
In a BBC interview last night, asked what he would do if he were handed a pearl-handled revolver, he replied: "I used to be in the Army, and I know how to use these things, and they never point back at me." He said that the Tories could either sell their new policies to the public or "argue themselves into a hole for the next six months", adding: "If you think there is another way, you are living in cloud-cuckoo land."
Asked how he would react if he was told that the necessary 25 MPs called for a vote of confidence in him, Mr Duncan Smith said: "Go and put them in a telephone box." One Duncan Smith aide said: "He is appalled that a few malcontents have been trying to destabilise him and drive him out. His message to them is that he will not be cowed. They will have to come and get him."
The Tory leader tried to rally the party behind him by launching a strong personal attack on Tony Blair, whom he will brand a "liar."
He said: "During the next election, don't be surprised when Labour plays dirty. A Prime Minister that lied about his own record won't hesitate to lie about us. A government machine willing to smear the Paddington train crash survivors and Dr Kelly won't think twice about smearing me. A political party prepared to use the tragedy of 11 September to bury bad news will do everything it can to hide the scale of its own failure."
Critics increased the pressure on Mr Duncan Smith to deliver the speech of his life today. Jonathan Steel, chairman of Beaconsfield Conservative Association, said that if it was "not a barnstormer", at least 25 MPs would trigger a confidence vote.
Marion Rix, who chairs the Norfolk South West constituency party, was rebuked by a senior Tory official after criticising Mr Duncan Smith.
She said: "At the end of the day, we are in the game of winning elections. The reality is that - at the moment - we don't look like we are going anywhere fast."
Mark Hudson, chairman of Sevenoaks Tories, who voted for Mr Duncan Smith in the 2001 leadership election, said: "The question is whether he can lead us to victory at the next election. Time is running out for him to demonstrate that."
Jonathan Marland, Tory candidate for Somerton and Frome at the last general election, said: "The mood of the conference is such that there is time for a new leader. You sense it as you walk through the corridors here. It is the subject on everyone's lips."
But Karen Lumley, who will fight Redditch in the next election, won a standing ovation at the conference when she told the leader's critics: "You think you are just undermining Iain Duncan Smith. But let me tell you, you are undermining me and undermining everyone in this conference hall."Reuse content