The onslaught came in broadsides from Sir Norman Fowler, the party chairman, and Virginia Bottomley, Secretary of State for Health, and in a 50-page Conservative Research Department pamphlet to be published at the Tories' Central Council Meeting in Plymouth today.
The Prime Minister and leading Cabinet members will address the key meeting in the Tory calendar, crucially timed this year in the run- up to the 5 May council elections and the contests for the European Parliament on 9 June.
The Liberal Democrats accused the Tories of choosing Plymouth because of mounting fears about their growing strength.
Sir Norman, however, said the Liberal Democrats had enjoyed a 'free ride' as the repository of the protest vote. 'We are exposing what their policies are.'
If the public really understood Liberal Democrat policies - 'carbon copies of Labour's' - they would 'run a mile,' Sir Norman said.
Mrs Bottomley accused the party of 'pandering to people's fears and prejudices' with a leaflet in Portsmouth claiming that pensioners and people on low incomes would be hit hard by prescription charge increases. She has sent a complaint to Mr Ashdown.
She said: 'Since pensioners and those on income support and Family Credit don't pay prescription charges, I'll be interested to know how he justifies such a wicked falsehood.'
Matthew Taylor, the Liberal Democrat campaigns spokesman, told a Westminster news conference that his party posed a real threat to the Tories at the forthcoming Eastleigh by-election, in Cornwall and Somerset in the European elections and across the country in the local elections.
'That is why they are going to Plymouth for their meeting. That is why they are attacking us on a daily basis, why we believe they are right to be worried.
'They used to say in war, don't fire until you see the whites of their eyes. The whites of the Conservatives' eyes are very apparent now.'
The Liberal Democrats have yet to win a Euro seat because support within the large constituencies is too thinly spread. But Paul Tyler, the party's rural affairs spokeman, said support had reached 'critical mass' in some areas.
He said: 'The Conservatives are so out of touch in the South-west that they are in danger of becoming electorally extinct.'
Sir Norman admitted yesterday that his party 'obviously faces challenges from the Liberals. It would be extraordinary if the Conservative party was complacent.'
Tory denunciation of the party reaches new heights in the booklet, Left-Wing Opportunities, which dismisses Mr Ashdown as given to 'cant and moralising - like a latter-day cut-price Gladstone'. The Liberal Democrats are a party of the left, without principles and composed of optimists, it says.