Ed Miliband's leadership has been dealt as fresh blow with the latest poll suggesting almost half of voters think he should be replaced before the general election.

Worse, 43% of Labour voters want to ditch him and the number who think he is ready to be prime minister has fallen further from 24% to 22% over the past year.

The survey, by Ipsos Mori for the London Evening Standard, comes on the heels of a separate poll showing Miliband's personal rating had slumped to a new low, putting him behind even Nick Clegg.

The ICM survey for the Guardian showed, while all leaders scored negatively on leadership, Miliband's net rating was minus 39% compared to Clegg's 37%.

However, both polls continued to show Labour narrowly ahead of the Tories, 3% in the latest, when it came to voting intentions, which raised the prospect that people might support Labour despite the 49% wanting Miliband ditched.

But it has inevitably raised the question of whether Labour could do better with another leader, on which the poll is far less helpful.

The figures show 15% of those polled said they would prefer David Miliband, who is not even an MP, while the next two candidates, Ed Balls and his wife Yvette Cooper only scored 3% each, while the vast majority recorded a "don't know", suggesting there is no realistic or obvious alternative candidate.

By contrast only 27% think the Tories should dump David Cameron.

In any case it is largely an academic exercise as no one believes Miliband will be replaced before the next general election, barring some major unforeseen event.

In fact, even though Clegg remains hugely unpopular, with 44% thinking he should be replaced, it is expected that all three major party leaders will take their troops into the 2015 poll.

The latest survey follows a series of PR disasters for the Labour leader including his awkward picture eating a bacon sandwich and his decision to pose with the Sun newspaper for the World Cup only to apologise the next day to Liverpool voters who have never forgiven the paper for its treatment of Hillsborough victims.

It is widely accepted in Labour ranks that Miliband has an "image issue" and may need someone to offer more professional advice on future photo calls and PR stunts, a role currently not filled with a specific individual.

Others, however, remember the disasters that struck Neil Kinnock and Gordon Brown when they were given such advice and appeared unnatural, even odd. They are urging the Labour leader not to worry about the polls and to be himself.

The idea that his geekiness and occasional awkwardness actually make him appear authentic and appealing has yet to be proved, however.