Tim Farron is one of eight remaining Lib Dem MPs, and one of two men along with Norman Lamb who want to succeed Nick Clegg as party leader.
In an interview with our sister paper i he said the Lib Dems had to ditch "Edwardian" style party structures that consisted of an HQ, staff and subs-paying members who go to conference once or twice a year.
"Obviously Lib Dems are more active than most but we need to be a movement," he said.
Farron, MP for Westmorland and Lonsdale and a former Lib Dem president, claimed that the party had erred under Clegg in championing its governing competence during the campaign - and that the way forward was to "fire up" 13,000 new and existing members with "doorstep politics".
With so few MPs remaining, the Lib Dems under Farron would also ditch the concept of having a full 'shadow' portfolio matched to government departments.
If it is anything to do with me we are not going to be appointing shadow cabinets and trying to shadow every single debate.
You pick a small number of issues – tackling poor housing or tackling waiting times in A&E. They are campaigns that we will run across the country in council chambers, in communities, in student unions, radio, television and social media.
Farron also floated the idea of Lib Dem and Labour peers blocking Conservative legislation in the House of Lords.
We will behave in a way that is respectful of the democratically elected Government although we are bound to acknowledge the fact that this this Government has one of the smallest mandates that I can think of.
Less than 25 per cent of the people north of the M25 voted for the party in power so that does sort of temper any mandate they may claim to have.
A new leader will be elected on July 16.
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