Keir Starmer's one-time rival for the Labour leadership today warned him the party faced "electoral suicide" if he didn't start setting out his plans to govern.
Rebecca Long-Bailey, who lost out in the 2020 race to succeed Jeremy Corbyn, also predicted the Tories had just 6 months to "change course" from their "budget for investment bankers" or lose power.
Speaking on the Mirror's News Agenda programme, the Salford and Eccles MP welcomed a poll showing Labour would win a 56-seat majority but said it wasn't set in stone.
She added: "One note of caution I'd issue to our leadership, I suppose, is don't just assume the Tories are going to mess up for the next couple of years."
"They're very good at getting their act together and running a good election campaign, trying to put out messages they think will be popular and appeal to people. What we need to do now is start offering out a vision and setting out our own radical policies, rather than just kind of hoping we can wait to the last minute and then sail in," said Long-Bailey.
"I think that would be suicidal fo the Labour Party, to assume the Tories will be this bad for that long."
With a party conference row brewing over proportional representation, Long-Bailey said electoral change was needed because the existing system was "a form of gerrymandering, for want of a better word".
But she warned that PR "creates quite volatile situations" and it was equally important to "democratise the economy".
She said: "How do you get workers on boards, so they have a voice at the table to shape how a company is run, and how much workers are paid? How do you democratise public services, bring water, rail, energy, and mail back into public ownership so people have a right to say how those companies are run in their interests, rather than the interests of shareholders? It's not just about how you vote, but every aspect of our lives."
