Nick Clegg has become the least popular party leader in modern British political history, according to a poll.
YouGov research for the Sunday Times found just 13% thought the Deputy Prime Minister was doing a good job - compared to 78% who said the opposite.
The Liberal Democrat's -65% rating is even worse than Gordon Brown's -62% at the height of the credit crunch crisis in 2008.
The figures are a remarkable turnaround since the 2010 general election, when Mr Clegg had 74% approval and was hailed as the most popular leader since Churchill.
The Lib Dems descended into bitter infighting in the wake of disastrous local and European election results, with Business Secretary Vince Cable forced to deny he was part of a plot to oust the leader.
The newspaper reported that Lib Dem activists have now begun no-confidence proceedings against Mr Clegg in 190 local associations. They need to be successful in 75 to trigger a leadership contest.
Former Liberal Democrat leader Lord Ashdown said it was clear there had been a "plot of deep malice" to defenestrate Mr Clegg.
Lord Oakeshott - a close friend of Mr Cable - resigned from the party last week after admitting he had commissioned research on how it would fare under a different leader. In a parting shot, he warned that the Lib Dems were heading for "disaster" with the Deputy Prime Minister in charge.
"What has happened after these elections has made a bad situation worse," Lord Ashdown said.
"We now know there has been a plot of deep malice to try and remove the leader.
"I have got a very clear message for the party, and that is anything you do now which is not getting out on the streets campaigning in the context of the next general election - which is where we can put our proposition of how we have behaved in government behind a fine leader and I think a fine record - is a distraction and a dangerous distraction."
Asked if he thought Mr Cable was involved in the plot, Lord Ashdown replied: "He says not, Nick says he wasn't."
However, he referred to Shakespeare's Othello - who was betrayed by his confidante Iago - in offering some advice to the Business Secretary.
"One of the rules of politics is choose your Iagos carefully," he said.
Lord Ashdown said he had told Lord Oakeshott before the elections: "'Matthew, you are famous for making difficult days for the party more difficult. If you do that again after May 23 I will first of all remove your head and then your testicles.'
"He dashed off to the press and said, 'oh Paddy Ashdown's being nasty to me, he's a member of the special forces, maybe he can really do this.'
"He said 'I'm terribly shocked', and I think my answer to that is 'Ah, diddums'.
"I don't have to do anything to Matthew Oakeshott because the party's done it for him."
Lord Ashdown conceded Ukip leader Nigel Farage "had a point" about the lack of democratic accountability in the EU.
But he insisted the Lib Dems should keep campaigning as the pro-European "party of in".
"I think Europe is the greatest idea of our time," the peer said.
"I think in a globalised world, with an America now looking across the Pacific more than across the Atlantic, with a highly assertive and aggressive Russian president on our eastern borders, with chaos in the Magreb and the Arab world to our south, Europe pooling its sovereignty to work together to deliver to our citizens the security, the jobs, the cleaner environment, the crime free streets... is the greatest idea to come out of Europe of our time.
"The answer is not to throw out the baby with the bathwater. The answer is not because we have not created a perfect democratic linkage, we therefore get rid of Europe."
Lord Ashdown said it would be "madness" to abandon the EU and return to the "perfect sovereignty of corks floating around behind other people's ocean liners".