Conservative Party leadership contestants Kenneth Clarke and Iain Duncan Smith held their final regional hustings in North Yorkshire last night.

After private meetings with Tory members in London, both candidates headed north to Harrogate to put forward their cases.

Last night, Mr Clarke's supporters seized on the latest turnout figures, which they believe put him on course to beat the favourite Mr Duncan Smith.

Nearly three-quarters of party members have voted in the postal ballot, which closes next Tuesday.

The high turnout was welcomed by both camps as a sign that whoever wins the battle to succeed William Hague will have a clear mandate to lead the party.

But a Clarke source said the figures were encouraging because the former Chancellor is seen as having the greater support among the grassroots of the party.

The Electoral Reform Ballot Services, which is conducting the ballot on behalf of the party, has received 235,558 papers - 74 per cent of eligible members.

It compares with a turnout figure of below 60 per cent in the 2001 General Election.