David Cameron: "We have to win this election house by house, street by street"
David Cameron has warned of the dangers of a hung parliament and said only a "decisive" Conservative government would "get the job done".
Polls for Sunday's papers suggest Lib Dem support rose after the TV debate.
Their leader Nick Clegg claimed "something exciting" was happening in politics as he campaigned in Surrey.
Gordon Brown did not mention the Lib Dems in his speech to Labour activists, but attacked the Tories who, he said, would "wreck" the recovery.
Mr Cameron warned of the consequences of a hung parliament - seen as more likely if there is a big rise in Lib Dem support - as he addressed people in Gloucester.
"A hung parliament would be a bunch of politicians haggling, not deciding.
"They would be fighting for their own interests, not fighting for your interests. They would not be making long-term decisions for the country's future, they would be making short-term decisions for their own future.
"The way we are going to get things done is to have a decisive Conservative government."
Gordon Brown, campaigning in Bedford, said the election was not about style and personality but about the big issues.
"Let's make sure we have the recovery and don't let the Conservatives wreck the recovery," he continued.
Although he did not mention the Lib Dems - whose campaign is based around "fairness" - Mr Brown did end his speech by insisting the Labour Party were "greatest force for fairness in the country".
Later Mr Brown continued his attack on Conservative policy, in a question and answer session in Milton Keynes, saying their plan to take £6bn out of the economy would put jobs at risk.
Mr Brown and Mr Cameron have both said Mr Clegg performed well in Thursday's televised prime ministerial debate, but senior Labour and Conservative figures are now warning the Liberal Democrat leader to expect a lot more scrutiny between now and polling day.
In an e-mail to be sent to Tory activists George Osborne said the Lib Dems would face real questions over their policies on immigration, alternatives to Trident, prison sentences and the economy.
The shadow chancellor wrote: "How can they control immigration by giving an amnesty for illegal immigrants? If they want to scrap Trident what is their alternative
"If they want to scrap prison sentences under six months how many burglars and drug dealers will be walking the streets as a result? And how would they get the economy moving with new taxes on businesses and entrepreneurs?"
Mr Clegg, on a visit to Kingston Hospital, in south west London with his wife Miriam, said he welcomed any focus on his party's policies, arguing the election must be a "contest of ideas, not advertising budgets".
Nick Clegg's TV performance has thrust him into the media spotlight
He said: "I think a growing number of people are starting to hope that real change and that real fairness is finally possible in Britain."
The SNP's leader Alex Salmond said Mr Cameron was in a "blue funk" over his comments on a hung parliament, saying it was something to welcome not fear.
"It is increasingly clear the more people contemplate a Labour or Tory victory the less they like what they see."
A poll for Sunday's Mirror and the Independent on Sunday, carried out by ComRes after the debate, suggests Labour are in third place on 27%, with the Lib Dems second with 29% and the Conservatives on 31%, with others on 13%. It spoke to 1,006 adults on Friday and Saturday.
This comes after a poll for Saturday's Sun, carried out by YouGov also after the debate, indicated Labour are in third place on 28%, with the Lib Dems on 30% and the Conservatives on 33%.
Meanwhile, an ICM poll for the Sunday Telegraph, carried out on Wednesday and Thursday, puts the Lib Dems on 27%, with Labour on 29% and the Conservatives on 34%. ICM spoke to 1,033 adults by telephone.
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