Clegg says 'something exciting' happening in politics
Nick Clegg: Election campaign "should be a contest of ideas"
Nick Clegg says people believe "something exciting" is happening in the election, as polls suggest the Lib Dems were boosted by the TV debate.
One survey indicates they are ahead of Labour, while another suggests they have closed the gap to two points.
Mr Clegg said people were "starting to hope real change" was possible.
The Tories warned of a hung parliament, seen as more likely if Lib Dem support increases, while Labour said Lib Dem policies would get more scrutiny.
The ComRes poll for the Sunday Mirror and Independent on Sunday puts the Conservatives on 31, the Lib Dems on 29 and Labour on 27. The poll of 1,006 people was conducted on on 16 and 17 April.
David Cameron met parents at a nursery in Chipping Norton
Meanwhile, an ICM poll for the Sunday Telegraph puts the Conservatives on 34, Labour on 29 and the Lib Dems on 27. It says this is the Conservatives' lowest rating in an ICM poll since September 2007.
And the newspaper says this is the first time an ICM poll has shown such a narrow gap between the three main parties since September 2003. The majority of the 1,033 respondents were polled before Thursday's debate.
Meanwhile, Labour and the Conservatives vowed to scrutinise their policies closer, with Labour criticising the party's policy on Trident.
The Liberal Democrat leader, on a visit to Kingston Hospital, said: "I think change, real change is more possible than people think when a growing number of people start thinking, believing, that maybe we can do things differently.
"I think that is what is starting. I can't predict what is going to happen in the election campaign, but I think something exciting is starting to happen."
Asked if by "something different" he meant a formal coalition, he said: "I don't think we should put the cart before the horse."
But he said that more people were turning away from the "old politics" of Labour and the Conservatives.
Mr Cameron told people in Gloucester that 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," he went on.
"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 met local party activists in Milton Keynes
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".
But earlier Defence Secretary Bob Ainsworth criticised the Lib Dem's policy on Trident as "ridiculous".
The Lib Dems "rule out like-for-like" replacement, instead saying they will seek "alternatives" and support efforts at multilateral nuclear disarmament.
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