A report in the House Magazine for MPs says the party, which had 2.8m members in 1953, could have fewer than 100,000 members by the end of the decade unless urgent action is taken.
Mr Hanley will announce plans at the conference to boost the membership, currently estimated at 500,000. These include allocating pounds 1m to raise the number of agents by 50 per cent, to 300.
But the report, by Patrick Seyd and Paul Whiteley of the University of Sheffield, based on an earlier study, suggests the decline in Tory support will be difficult to reverse.
'If the Conservative Party wants to retain its hitherto dominant position in British electoral politics, it needs to develop a strategy for reviving the local parties with some urgency,' they said.
The key problem is the ageing face of Tory grassroots supporters - the average age of members is 62, and 43 per cent are over 65.
'Few people will want to join and be active if the local Conservative Association looks like a club for retired people,' they said.Reuse content