Ed Miliband has insisted he is “not countenancing defeat” as he embarked on the final push of the election campaign.
The “optimistic” Labour leader said he would go “right down to the wire” to persuade wavering voters in the remaining hours before polls open.
But he again repeatedly refused to be drawn on what form negotiations might take in the event of a hung parliament.
Mr Miliband said: “I’m not countenancing defeat. I’m focusing on winning the election.”
The Labour leader had enjoyed a largely gaffe-free campaign until the unveiling of an 8ft 6in stone carved with the party’s six key election pledges, which was quickly mocked and dubbed the “Edstone”.
Defending the stunt, he told the programme he would “definitely claim the credit for it” but said “somebody in our campaign” had come up with the “great idea”.
He said: “I think the Ed... the stone is absolutely the right thing to do.”
Told the stone made his awkward bacon sandwich photo opportunity look like good PR, Mr Miliband replied: “Ooh, thank you very much.”
Mr Miliband is campaigning across Lancashire and Yorkshire where he is claiming that a fresh coalition between the Conservatives and Liberal Democrats poses a “huge risk” to working families.
He is accusing both parties of defending the non-dom tax avoidance rule and preparing to “protect the privileged few” if they remain in power.
“I’m going right up to the line, right down to the wire talking about the issues that matter to the British people, which is the NHS, their family finances, whether they can pay the bills at the end of the month, those bread-and-butter issues that matter most to the British people,” he told broadcasters.
Asked if he really believes he is going to be prime minister, he replied: “I’m optimistic but it will be in the hands of the people come tomorrow and I know the people will make the right judgment.
“And, I hope people make a judgment on the basis of what’s best for them and their family because I’m not just asking people to vote Labour, I’m asking people to vote to put their family first in this election.
“I think on the ballot paper is the National Health Service, tax credits and child benefits, family finances, our young people, and that’s why I ask people to vote Labour.”
Deputy leader Harriet Harman insisted Labour was not involved in discussions with other parties about possible post-election pacts.
Ms Harman told Sky News: “We are not having discussions behind closed doors with anybody from other parties, because our agreement and our discussion is with the British people. That’s who we are asking to vote for us.
“Our commitment and our contract is with them, not some shady deals that we do now behind closed doors.”
Ms Harman defended the “Edstone” and Mr Miliband’s decision to do an interview with comedian Russell Brand - though she briefly forgot the film star’s name.
“A lot of people thought our pledge card was a ridiculous idea at the time, and it was a very good idea,” she said.
“I think it’s very good to bring to people’s attention the absolute clarity of the key things that Ed Miliband is determined to commit to.
“People can knock it if they want, I think they are wrong to knock the fact that he did an interview with... umm... whatshisname... Russell Brand. I think it was really important he did that.
“People can knock it, but he is out there, putting out the message, whether it’s in discussion with Russell Brand or whether it’s on a tablet of stone or on a pledge card.”