Labour leader Ed Miliband should not lead the party into the next general election, according to a third of the party's supporters.
A poll in The Mirror, carried out by ICM Research, piles further pressure on Miliband as he tries to convince voters he should be the next prime minster.
According to the figures, fewer than half (46%) of those who voted Labour in the 2010 general election think Miliband should be in charge for the next national poll in 2015, while 34% think he should not.
Over 40% of Labour supporters are dissatisfied with Miliband's performance as leader, while just one in five (21%) believe he is doing an adequate job.
Miliband's Shadow Cabinet also came in for criticism, with 72% of the ICM respondents suggesting the leader is not getting enough support from his front bench.
During the summer Labour has received criticism for its performance, with critics accusing the party of not doing enough to make its voice heard.
Concerns over Labour's policy direction have fuelled calls for a reshuffle by the leader. But that may not be so easy, with a lack of big names ready to take on shadow briefs on the front bench.
Writing on the website Political Betting, Mike Smithson said: "The only saving grace for Ed is that the poll finds no clear alternative. Amongst Lab voters 28% say he should lead party at GE2015 with the former MP, David Miliband backed by 18%. Next one down is Harriet Harman on 5%.
"In a way that suggests that this is more than just a Miliband matter, but a reflection on the weakness of the party leadership as a whole. There are no big figures who command respect or even are recognised."
YouGov's Anthony Wells said recent polls point to a trend for Miliband.
Writing on UK Polling Report, he said: "What we can tell is that perceptions of Miliband seem to be heading in the wrong direction. The proportion of people thinking he is a weak leader up to 51% (from 47% in July and 37% last September), the percentage thinking he is not up to the job of Prime Minister is up to 62%, from 57% in July, 51% in May. Whether this actually matters or not is a different question."
But the gloomy ICM figures are not the whole picture for the party. Its lead over the Conservatives remains around six points, but some say this is too low for a mid-term Opposition lead.
ICM polled 1,435 adults between 16 and 18 August.