The Conservatives will be out of power after 2015, Ed Miliband has predicted for the first time.
The Labour leader's confident prediction comes after a week which has seen the Tories' reputation marred by the cash-for-access scandal and its leaders accused of being out of touch over 'pastygate'.
But it was also the week in which George Galloway upset Labour's candidate in the Bradford West by-election, in a major setback for Mr Miliband's leadership.
"I think it is going to be remembered for the end of the Cameron project," Mr Miliband told the Observer newspaper.
"Thursday night was a very bad result [for Labour] but there is a big picture about where politics is and I think people will look back on the last few weeks and say, 'that was when the Cameron project hit the buffers and this was when Labour had their chance'."
Members of Mr Miliband's shadow Cabinet appeared more downbeat in media appearances on Sunday morning.
Shadow home secretary Yvette Cooper conceded on BBC1's The Andrew Marr Show: "We've got much further to go. We've got to earn people's support."
Shadow foreign secretary Douglas Alexander, developing the point on Sky News' Murnaghan programme, added: "I think it reminds Labour of a broader lesson - it is not sufficient for Labour to win that the Conservatives are unpopular.
"It teaches us an important lesson that we need to not just be rooted in the communities that we represent but also be a party focused not just on amplifying anger in society but in delivering answers, being seen as a genuine alternative to a deeply unpopular Conservative government."
Mr Miliband remains upbeat, however. Left-wing parties are struggling at the ballot box across Europe but the Labour leader believes the current slump can be recovered from in the coming months and years.
"I have got MPs saying to me that people are switching over from Tory to Labour," he added.
"One swallow does not make a summer, but I think it is a very exciting and potentially positive time for progressive politics, and our job is to move into that space and that space is opening up."