David Cameron has said the Conservatives need a "decisive" victory on May 6 in order to keep Labour out of power.
Speaking in Swindon this morning, the Tory leader warned that a vote for the Liberal Democrats risked handing power to Gordon Brown in a hung Parliament.
"If you want to wake up on May 7 and be absolutely certain that you've got new leadership in this country and are not stuck with another five years of Gordon Brown, stuck with dithering and despair and depression, the only way to get that is a decisive Conservative vote," he said.
And he refused to accept that he had lost the first leaders' debate staged last Thursday.
"People will judge the debates, people will decide what matters in these debates. What I think matters the most is getting your case across about the change you want to bring," he said.
"Whether it's the need to control immigration, whether it's the need for a tougher approach on crime, whether it is how we improve our health service, on all of those subjects, people watching at home can hear how the potential leaders of our country actually believe about those things.”
He added: "If you want real change, if you want the job to be done, the only way to get it done is to have a Conservative government.
On the BBC television's Andrew Marr show this morning, Gordon Brown said the debate had “energised the campaign” and thrown the contest "wide open".
He said: "People thought it was a closed book to start with. I lost on presentation. I lost on style. Maybe I lost on smiling.
"Some may think I'm a sort of a tough headteacher, I don't know,” he said.
"But I've learned at the end of the debate, substance will come through."
"I think the Liberals have got to be exposed. They are going to cut child tax credits, they are going to cut the child trust fund, they have got a very strange proposal for the winter fuel allowance for pensioners that they want to introduce immediately," he said.
"I want a majority, and so obviously I am going to say that a hung parliament is a bad thing for this country because we need a majority.”
While Liberal Democrat leader Nick Clegg said that people were starting to believe there was a choice other than Labour or the Conservatives.
"A growing number of people are starting to hope, starting to believe a little door has opened, that maybe this time we can do things differently," he said.
But he warned that his party would become more of a target following the poll boost they received as a result of the leaders' debate.
"Of course they'll attack and of course they'll come up with all sorts of misleading claims. Of course the old parties will start lashing out now," he said.
A poll in the Times this morning put the Liberal Democrats on 29 per cent, one point behind Labour who are on 30 per cent. The Conservatives maintain their narow lead on 33 per cent.
Clegg has an astronomical approval rating of 72 per cent ahead of Cameron on 19 per cent and Brown on minus 18 per cent.
And a BPIX poll for The Mail on Sunday put the Liberal Democrats in the lead on 32 per cent, one point ahead of the Conservatives on 31, with Labour trailing third at 28.
