Mr Ashdown, at the head of an election campaign which ruthlessly targeted winnable seats and ignored hopeless cases, celebrated the election of 45 Liberal Democrat MPs compared with 20 at the last election. The Liberal Democrat leader pointed out that it was the best result for any third party since 1929.
While the Liberal Democrats' share of the national vote was slightly below the 18 per cent achieved in 1992, the focused nature of the election strategy enabled them to pick up most of the 50 seats they targeted. Party officials argued, however, that a fairer electoral system would have doubled the Liberal Democrat representation.
Mr Ashdown said: "The Conservatives have suffered an election catastrophe of earthquake proportions. No doubt they will now understand the injustice of the first past the post electoral system."
Mr Ashdown's aides emphasised Tony Blair's recently reaffirmed pledge to set up a commission to investigate proportional representation as a means of electing MPs.
The timetable agreed by both Labour and the Liberal Democrats would mean that a commission on the issue would report in a year's time and there would be a referendum on its recommendations within two years. Depending on the result of the plebiscite, the Liberal Democrats say that a new system would be in place by the next general election.
Mr Ashdown pointed out that two-thirds of the new House of Commons was committed to the establishment of the commission and that Liberal Democrat MPs would co-operate with the Government to ensure that the process went ahead as agreed.
The Liberal Democrat leader said his party would assist the new administration where that was possible and provide "vigorous opposition" when it was required. They would be a "constructive opposition".
He also said his party would now make a far more effective opposition than the Conservatives who would be preoccupied with internal arguments.
Asked by journalists at yesterday's final press conference what he thought of Mr Major's powers of leadership, Mr Ashdown said he had fought "an honourable - almost lonely campaign". And he added: "Anyone who has watched it cannot but admire his personal determination and his personal courage. It has been a remarkable sight. He is a decent man leading what is a terrible party."
Liberal Democrat strategists yesterday claimed the result as a triumph for its policy of targeting marginal constituencies. They had also tried to persuade the electorate that they could be "winners" - emphasising the fact that they were the second largest party in local government.
Chris Rennard, the party's director of campaigns and elections, said that party had also clarified what it stood for. In the 1992, the Liberal Democrats had emphasised their policies on constitutional reform and the doctrine of "equidistance" between Labour and Conservatives. This time they had hammered home their commitment to education and health and were open about the need for more tax to finance it.
Mr Ashdown was prominent on the hustings and his reputation for integrity and his tireless campaigning had proved a vote-winner, Mr Rennard said.
In Taunton, for example, the Liberal Democrats were 3,336 behind the Tories in the 1992 election, securing 41 per cent of the vote, compared with the Tories' 46 per cent. This time, Jackie Ballard, the Liberal Democrat candidate, got 43 per cent of the vote to the Tories' 39 per cent. "We knew we could win if people thought we could win," said Mr Rennard.
In some editions yesterday, we wrongly reported that Simon Hughes, the Liberal Democrats' health spokesman, had lost his Southwark North and Bermondsey seat. In fact, Mr Hughes won by a margin of 3,400 over Labour.