Mr Darling compares Labour to a losing football team
Chancellor Alistair Darling has urged Labour to "come out fighting", comparing his party to a football team which has "lost the will to live".
Speaking to the Observer on the eve of Labour's last annual conference before the general election, he says every minister should take responsibility.
Meanwhile, the prime minister has fought back against critics of the government's handling of the economy.
He has promised a new legal commitment to halving the public debt by 2015.
In the newspaper interview, Mr Darling accuses Labour - from the prime minister and himself down - of appearing to concede the advantage to the Conservatives without a fight.
"From the prime minister, the chancellor, every government minister. It is all our responsibilities," he says.
Likening the party to a losing football side who have allowed their heads to drop well before the final whistle, he says: "We don't look as if we have got fire in our bellies."
It comes as an ICM poll for the News of the World finds more than half of those surveyed still think Gordon Brown could win the next election.
Some 11% of the 1,003 adults say Labour has a good chance of winning with Mr Brown and 48% say it has a slim chance. But 41% think it probably or definitely has no chance, the poll finds.
In an interview with the newspaper, Mr Brown says he can get the economy under control without massive cuts.
As well as pledging to cut Britain's £175bn deficit, he says: "We should protect frontline services and continue to invest in a high growth, high employment future."
In a separate interview in the Sunday Telegraph, Mr Brown says he wants to represent the interests of the UK's "squeezed middle classes" affected by the recession.
"These are the people who I identify with and understand the problems they face," he tells the paper.
Mr Darling is one of several senior Labour figures who have sought to rally the party.
Business Secretary Lord Mandelson has insisted Labour should not be written off, telling the Sunday Mirror: "This election is not in the bag - neither for us, nor the Tories.
"Every day we face in one way or another attempts to write Labour off or pretend that some of us are preparing for defeat. That's not my belief."
But in an interview with the Independent on Sunday, Foreign Secretary David Miliband urged the prime minister to look "forwards not backwards" and "show what we stand for for the future".
Wales Secretary Peter Hain is expected to tell the conference that the key to the election is changing voters' perceptions from "are you fed up with Labour?" to "do you really trust the Tories with your jobs, mortgages, families and pensions?"
On Saturday, former Deputy Prime Minister John Prescott urged Labour supporters to "stop complaining and get campaigning".
Mr Brown was greeted by cheering Labour activists as he arrived in Brighton for the conference on Saturday.
Accompanied by his wife Sarah, a beaming Mr Brown shook hands with his deputy, Harriet Harman, and Labour General Secretary Ray Collins as he arrived at his hotel.
BBC political correspondent Ben Wright said fixing the economy will be a key theme of the week, with Mr Brown facing the challenge of convincing depressed party members that the Conservatives do not have the next election in the bag.
Mr Brown is expected to unveil in his speech on Tuesday a promise that patients in England will get key cancer tests within two weeks of seeing their GP - funded from savings worth £1bn from the NHS's capital budget over five years.
Our correspondent says the prime minister is also expected to claim credit for economic recovery during his address to delegates.