Jeremy Corbyn: 30% of Labour voters do not think he will lead party at next election – poll

Almost a third of Labour supporters do not think that Jeremy Corbyn will lead Labour into the next general election, according to a new Opinium/Observer poll to mark the Labour leader’s first 100 days in office.

A majority of likely voters (57%) – including 30% of Labour supporters – said they did not expect Corbyn to be in charge at the 2020 election.

Many of the survey’s findings will make grim reading for Labour MPs and supporters, three and a half months after Corbyn won an extraordinary mandate from party supporters in the leadership election to succeed Ed Miliband.

He reaches the 100th day of what has been a turbulent start to his leadership on Monday.

When asked who they believed would make the best prime minister, 41% of all questioned named Cameron, compared with just 20% who chose Corbyn. Only 54% of Labour voters thought Corbyn would be the best PM, whereas 91% of Tory voters selected Cameron.

The poll put the Conservatives on 38%, eight points ahead of Labour, which is on 30%. A month ago the gap was 7%.

The UK Independence party (Ukip), on 16%, has dropped only one point since last month, despite rumblings over the leadership of Nigel Farage.

The SNP and the Liberal Democrats are unchanged since November on 6% and 5% respectively, while the Greens have risen two percentage points to 5% in a month. An Opinium poll on 17 December 2010, at almost the same stage of Ed Miliband’s leadership, showed Labour and the Conservatives tied on 37%.

However, while the poll reflects widespread doubts over Corbyn’s electability as prime minister, it shows that the Islington North MP has characteristics that appeal to the public. Over half of voters think that he stands by his principles: 56% of respondents agreed that Jeremy Corbyn “sticks to his principles rather than just saying what people want to hear”, compared with 24% who disagreed. Only 34% of likely voters felt the statement was true of David Cameron.

The public also has concerns about the media’s treatment of the new Labour leader. Half of all voters think that Corbyn is treated unfairly by the media, with the proportion rising to just over two thirds (68%) among Labour voters. Voters are more divided on whether Labour party members and MPs treat Corbyn fairly, with 37% thinking he has received fair treatment and 40% saying he has been treated unfairly.

The poll also asked voters to choose who they thought would be the better prime minister out of Jeremy Corbyn and three plausible Conservative successors to David Cameron, who has made clear that he will stand down at the next general election.

Of the three, Boris Johnson fared best. In a Corbyn contest between the Mayor of London and Corbyn, 34% of voters favoured Johnson against 23% for Corbyn. When Corbyn was pitted against Theresa May, 29% said the current Home Secretary would be the better PM against 23% who named Corbyn. George Osborne, the chancellor, fared worst, with just 24% of voters judging him the best prime minister against 21% for Corbyn.

Opinium conducted 1,936 online interviews between 15 and 18 December.