Supporters of Mr Iain Duncan Smith confidently predict he will be declared leader of the Conservative Party on Wednesday night. And he moved yesterday to allay fears of continuing party divisions over Europe, promising "tolerance" of pro-European colleagues after a warning that he could not assume their automatic loyalty because of his own record as a Euro-dissident.
The stark warning came from one of the party's elder statesmen, Lord Hurd - who, as Mr Douglas Hurd, was foreign secretary - fuelling speculation that Mr Duncan Smith could face open rebellion by supporters of Mr Kenneth Clarke.
Mr Clarke will continue campaigning even as the final ballots are returned this afternoon. He maintains that his chances of winning have been increased by indications that some 80 per cent of the party's estimated 318,000 members have taken part in the election of Mr William Hague's successor.
Having started the contest as the bookmaker's favourite, Mr Clarke finishes the outsider at 5-2 against Mr Duncan Smith, who entered the race as outsider at 25-1.
Mr Clarke has expressed confidence that the party's "silent majority" is less concerned with the European issue than with re-connecting with lost voters and preparing for a return to power. However a survey of late voters for yesterday's Sunday Times suggested they were backing Mr Duncan Smith by a margin of two to one.
Cautious members of the "IDS" team, while confident of victory, have told The Irish Times they believe the final margin may well be narrower than predicted. At the same time - while acknowledging that polling of this largely unknown electorate is unproven - they maintain there is no evidence of any significant gap between the opinion of the Euro-sceptic majority of Tory MPs and the grass-roots members.
Insistent that he can unite both wings of the party, Mr Duncan Smith's campaign manager, Mr Bernard Jenkins, promised "tolerance" of pro-European MPs and said they would not be expected to vote against their conscience.
The promise followed Lord Hurd's warning that "there will be continuing divisions because people will follow their convictions" as Mr Duncan Smith had done in opposing Mr John Major's government over the Masstricht Treaty.
Referring to the divisions which have tormented the party over the past 10 years, Lord Hurd told the Sunday Telegraph: "It will not be resolved by this election and whoever is elected will have to manage the divisions and drain the poison away. Iain Duncan Smith made his reputation by following his own convictions, certainly, but by undermining, in concert with the Labour Party, what we were trying to do in Europe. He can't really call on any automatic loyalty against that background."
A front-bencher, Mr David Willets - who backed Mr Michael Portillo but has not revealed which of the two remaining contenders he supports - said whoever won was entitled to the loyalty of the entire party.
Meanwhile, the shadow home secretary, Ms Ann Widdecombe reiterated her support for Mr Clarke. It came despite a warning from the former home secretary, Mr Michael Howard, a Duncan Smith supporter, that the Blair government would exploit a Clarke victory by tabling votes to highlight the contrast between his well-known enthusiasm for the EU and the euro and the overwhelming euroscepticism of his parliamentary party.