As the leadership race began in earnest, he made clear it was time for the party to move "beyond the threshold" and into power at a national level. His words were seen as a veiled warning to Charles Kennedy, front- runner in the crowded leadership race, who has expressed doubts over the "project" to extend co- operation with Labour.
Mr Ashdown said he had mapped out a clear route ahead for the Liberal Democrats during the past 11 years but it was up to his successor and the party to decide whether to follow that direction.
"What I know is this: the party has a choice to make; it will make it in the context of the leadership election and the choice that is open to it is to continue the thing we have done over the last 11 years, to move from the wilderness in politics into the process of handling power and therefore delivering things for our citizens which are of benefit to them," Mr Ashdown told BBC Radio 4's Today programme.
"Over this period we have substantially been a force which brings about change and modernisation to our constitution and our institutions, and I want to see us continue down that route." On the first day of the leadership race Mr Kennedy's campaign was boosted when Baroness Williams of Crosby, one of the four founding members of the SDP, publicly endorsed his campaign. "He is a man of great courage, because I saw him as the person who was the anchor in allowing our party to move ahead to the merger that created the Liberal Democrats and he played a key role in that," she said. Lady Williams said the relationship between the Liberal Democrats and Labour worked well in respect of Europe and constitutional reform.
"Charles would see, as I do, the need to continue with those areas of collaboration I have described, which are absolutely crucial; they are about the whole future of the country and its relation to Europe but I think he would want to maintain a distance when it comes to domestic policy."
Other candidates who declared their ambition yesterday to become party leader were Jackie Ballard, Malcolm Bruce, David Rendel, Simon Hughes and Don Foster.
Apart from Mr Foster and Mr Bruce, the other candidates will seek to appeal to the left wing of the party, which is sceptical of closer co- operation with Labour.
Mr Foster is a supporter of the "project" and Mr Bruce said he was not opposed to closer links. "Without equivocation, I take up the challenge of greater co-operation set out by Paddy. Our members did not join the Liberal Democrats for yah-boo politics. It's simply common sense to work with others to deliver the things we want and the country needs," Mr Foster said.
But it was Ms Ballard, who became an MP only in 1997, who stole the attention yesterday when she launched her campaign under the slogan "Jackie B - who cares wins", even before Mr Ashdown handed in his letter of resignation to the party president, Baroness Maddock. Ms Ballard and her entourage travelled in a helicopter from her Taunton constituency to a Westminster press conference. She then flew by jet to Scotland for another media launch and back to Manchester for her final campaign event of the day.
Dismissing any idea that Mr Kennedy was the front-runner, she said: "The 90,000 members of the party are an unknown quantity to all of us, so I don't accept that anyone is out in the front at the moment."
Review, page 3
Contenders For Leading the PArty Into the New Millennium
Name: Malcolm Bruce, MP for Gordon since 1983
Qualifications for the job: very experienced, fairly high public profile as Treasury spokesman,
Ideological stance: describes himself as a genuine radical in favour of "devolving up to a third of all public spending to local and regional government". Does not rule out further co-operation with Labour
Odds: not taken
Success rating: Worthy but dull
Name: Jackie Ballard, MP for Taunton since 1997
Qualifications for the job: strong links with the grass roots, effective, principled campaignerIdeological stance: against poverty, for a better environment, and civil liberties. Sceptical about close link with Labour
Success rating: inexperienced but strong candidate for deputy. Supporters describe contest as "Snow-White and the six dwarfs"
Name: Charles Kennedy, MP for Ross, Skye and Inverness West since 1983
Qualifications for the job: Highest public profile of all the candidates with influential backers. "Natural heir" to Paddy Ashdown
Ideological stance: Has doubts over the "project" of co-operation with Labour beyond constitutional issues. Also wants to reach out to pro-European Tories
Success rating: Clear favourite
Name:David Rendel, MP for Newbury since 1993
Qualifications for the job: Regards himself as the "activists' choice" in touch with Liberal instincts
Ideological stance: Sceptical about the co-operation project, believes there should be no "no-go" areas for the party
Success rating: Lacks charisma, but no shortage of self-confidence
Name: Simon Hughes, MP for Southwark and Bermondsey since 1983
Qualifications for the job: Effective health spokesman with strong power base in London
Ideological stance: Sees himself as "unity candidate" who supports co-operation with Labour but would make the joint cabinet committee more accountable to grass roots
Success rating: Too left-wing
Name: Don Foster, MP for Bath since 1992
Qualifications for the job: Popular across all parties, imaginative education spokesman, experienced in local government
Ideological stance: Supports the Ashdown project and would endorse closer links with Labour
Success rating: Too "pro-project" to win over grass roots. Opponents refer to his supporters as "projectphiles"