Howard is MPs' favourite

Michael Howard was this afternoon the runaway favourite to inherit the Tory crown as MPs limbered up for a full scale leadership battle.

But hopes for a smooth takeover in the event of Iain Duncan Smith losing tonight's vote of confidence was jolted by news that the campaign is likely to be long and gruelling.

Amid scenes of confusion and acrimony, party managers suddenly ditched plans for a high-speed timetable that could have produced a result within days. Instead, contenders will have until Thursday of next week to decide whether to fight.

At least four were expected to go forward - shadow chancellor Mr Howard, shadow deputy prime minister David Davis, the party's deputy leader Michael Ancram and shadow trade and industry shadow secretary Tim Yeo.

Others, headed by former chancellor Kenneth Clarke and ex-defence secretary Michael Portillo were hovering in the wings.

The first ballot of MPs to find a new leader would be scheduled for Tuesday, 11 November. And there was a real prospect that the two-stage election, first by MPs days. Instead, contenders will have until Thursday of next week to decide whether to fight.

At least four were expected to go forward - shadow chancellor Mr Howard, shadow deputy prime minister David Davis, the party's deputy leader Michael Ancram and shadow trade and industry shadow secretary Tim Yeo.

Others, headed by former chancellor Kenneth Clarke and exdefence secretary Michael Portillo were hovering in the wings.

The first ballot of MPs to find a new leader would be scheduled for Tuesday, 11 November. And there was a real prospect that the twostage election, first by MPs and then by the grassroots membership, could run until Christmas.

Some MPs were hoping to cut this short with a deal which would see Mr Howard given a " coronation" as leader with Mr Davis, seen as his most dangerous rival, agreeing-to serve as his deputy. But there was no sign that the two contenders were ready to agree with that as the Davis camp prepared for a campaign that could be launched as early as tonight.

Mr Duncan Smith delivered a last-ditch appeal to the backbench 1922 Committee as they prepared to vote. He ended a passionate plea with the words: "My future is in your hands." One veteran MP said: "It was a good, serious speech, but of course it won't save him."

Mr Howard's supporters were planning to get his bandwagon rolling at maximum speed. But they uneasily remembered the fate of Mr Portillo in the last contest, two years ago. He, too, started out as overwhelming favourite and ended up in third place.

The executive of the 1922 Committee, now effectively running the party, had originally planned to give contenders less than 24 hours to decide whether to take the plunge, with nominations closing at noon tomorrow. Then, amid near-panic, it was pointed out that this could look like indecent haste, not least because tomorrow morning all the main players will be at the memorial service for Sir Denis Thatcher. It was decided to delay the whole process by one week.

Mr Duncan Smith's supporters were still claiming he would at least come close to securing the 83 votes he needs.

But an explosive warning put him on notice that even if he wins, the revolt against his leadership will go on.

The critics said that it would not be good enough for the Tory leader Tory leader to scrape home with the backing of a narrow majority of MPs, the best result his backers were hoping for.

And there were suggestions that if Mr Duncan Smith did decide to cling on, with little more than half his Westminster troops behind him, there would be mass resignations from the shadow cabinet.