Labour should be "absolutely steaming ahead" with a 15-point lead in the local elections due to Conservative disarray, a former shadow cabinet minister has said.
Chris Leslie suggested the Opposition should be performing better in May than the equivalent elections in 2011, when former leader Ed Miliband had an opinion poll lead of up to 10%, given the Government is "on the floor so badly".
But Leslie insisted he did not want to "pre-empt any bad results" by suggesting what should happen to Jeremy Corbyn if his expectations are not met next month.
The former minister added Labour needs to focus on "getting out of protest mode" and starting to view itself as an alternative government.
Leslie, who served as shadow chancellor until September 2015, also urged the entire Labour leadership to campaign for Britain to remain in the EU and tie these efforts to local election campaigning across the UK.
He welcomed Corbyn's first intervention in the referendum campaign but warned this should not be a "tick-box exercise".
Appearing on Murnaghan on Sky News, Leslie said: "People make their minds up on the referendum over a course of time, it's not just something that will come at the last minute, so I think we have to run these things in parallel and I think people will get a sense of the vibe, the pheromones that leaders send out on these particular issues.
"If there is a sense of equivocation that somehow the heart isn't in it then people will say maybe there are reasons not to back this particular cause.
"So yes, let's focus and win on those local elections - we've got to have real progress made there and of course we should be absolutely steaming ahead given how bad the Conservatives are doing, I've never known a period of time when the Conservative Party has been in such disarray, devouring itself with resignations and rebellions on the Conservative benches on education and all sorts of things, we should be 10, 15 points ahead in the polls.
"Those local elections ought to be strong for us but let's not neglect the bigger strategic question facing Britain in the future.
"It's not just for prime ministers to take leads on these sorts of things. It's for leaders of all the main political parties because that's where the votes to remain will have to come from."
He added: "I think if you look back to where Ed Miliband was after 2011, which is the sort of equivalent period, we had eight, nine, 10% opinion poll lead. Today we're five points behind.
"Opinion polls come and go of course but we really ought to be doing better. I've never known a time when the Conservatives have been on the floor so badly."
Leslie earlier said of Corbyn's first EU speech: "I think my point would be it can't be a one-off. There's no point sort of having a tick-box exercise.
"The whole of the Labour leadership has to be consistently campaigning on this. There shouldn't be any question at all about the Labour Party supporting Britain's place in Europe."
Leslie praised the actions of Labour MP Alan Johnson, who is heading his party's campaign to remain, shadow foreign secretary Hilary Benn and shadow business secretary Angela Eagle.
He added: "I'd quite like to see John McDonnell, as the shadow chancellor, actually talk about the European Union. So there's a lot of things I think still need to be done.
"We can't just sort of leave it to one side, 'Oh a speech has been given, move on', this has got to be surely the top priority for all the political party leaders given the risk to our country."