With the Lib Dems enjoying a surge in the polls, many Conservative-supporting newspapers are filling their pages with stories critical of Clegg.
The Daily Telegraph reported that Clegg is 'under pressure to explain why money from party donors was paid directly into his private bank account'.
According to The Telegraph, Clegg was paid regular monthly sums by three senior businessmen during 2006.
Diageo communications director Ian Wright and KPMG head of public affairs Neil Sherlock were named as two of the Lib Dem donors paying funds into Clegg's private account.
Neither Wright or Sherlock could be reached as PRWeek went to press. The third named donor in the story was Michael Young, a former gold mining executive.
Last night, the three all admitted paying the money into Clegg's bank account. They said that the money they donated was to help fund a member of staff in Clegg's parliamentary office.
But Clegg insisted he had done nothing wrong. Speaking in Bristol ahead of tonight's general election debate, he told Sky News: ‘I received money from three friends which was properly given, properly received, properly declared, properly used to pay for part of the salary of a member of my staff. Any suggestion I did anything wrong is out of order and I'm going to publish the figures to prove it.'
The money was not used for personal spending and only subsidised his parliamentary work, said Clegg.
As Lib Dem supporters expressed outrage at the treatment dished out to Clegg in some sections of the media this morning, Tory blogger Iain Dale was also highly critical.
Writing on his blog, he said: ‘What a terrible indictment of the British press we see this morning. The Mail runs a spurious story about Nick Clegg making a supposed Nazi slur against Britain. The Express reckons he wants us to be overrun by immigrants. The Telegraph accuses him, of well, properly declaring donations made to him to employ a member of staff.'
Dale added: ‘I haven't seen The Sun yet, but judging by their tirades against him over the last few days, he will probably be accused of fathering Kerry Katona's latest child and then paying her to get rid of it.'
Meanwhile, the media attacks were parodied on Twitter, as the ‘hastag' #nickcleggsfault gained traction.
@mrchrisaddison: 'Tomorrow's Express headline: Clegg Tampered With Diana's Brakes'
@BrendanDodds: 'Nick Clegg did not fight in either world war'
@AIannucci: 'Nick Clegg lived in same town as a seriously ill man and never visited him, though he knows he has a spare kidney'
@urbancyclist: 'Nick Clegg was seen two weeks ago poking Eyjafjallajokull with a stick'
@sexyexecutive: 'The printer is out of both A3 and A4. I believe it was Nick Clegg from the third floor, printing out his party literature'
@JezzaLee: 'I have sweaty armpits today. Either #nickcleggsfault or my shirt's too tight/I've put on weight'
@JGurling: 'Someone swiped my personal copy of PR Week - that would be #nickcleggsfault'
Photo: Peter Crane