Keir Starmer is comfortably leading the race to take over from Jeremy Corbyn as leader of the Labour Party, a poll of party members has revealed.

The shadow Brexit secretary is ahead of Rebecca Long-Bailey, the shadow business secretary who appears to be a favourite of the left-wing of the party.

The YouGov survey of 1,059 members, who were polled between December 20 and 30. has Starmer out in front in each round under the party’s preferential voting system.

The system knocks out the least popular candidates until one has more than 50%. By the final round round of voting, Starmer secures 61% and Long-Bailey is on 39%.

The poll put Starmer on 31% for first choice votes, 20% backed Long-Bailey, Jess Phillips received 11%, and Clive Lewis and Yvette Cooper were the first choice for 7%, according to the poll.

Emily Thornberry was on 6% and Lisa Nandy was backed by 5% as first choice.

The election process will be launched next week, with the new leader taking over in March following Labour’s worst election performance since 1935.

But there are a series of caveats, not least that some possible candidates have not been included and others who have signalled their interest may not run.

Only the shadow foreign secretary Thornberry and the shadow treasury minister Lewis have officially said they want to run to be the next Labour leader.

Party chairman Ian Lavery has suggested he is considering running, and is not included in the YouGov poll, and Angelas Rayner is thought to be another strong contender, though HuffPost UK has reported she is likely to stand as deputy leader.

Professor Tim Bale of Queen Mary University of London, who jointly ran the poll with the University of Sussex, told The Guardian: “This is not shaping up to be a 2015-style Labour leadership contest.

“Unless potential candidates drop out before the start of voting, it may take a few rounds to decide the winner this time around.

“But it doesn’t look at the moment as if the winner will come from the left of the party.

“Right now anyway, Keir Starmer looks to be heading for a fairly emphatic victory.”

Brexit could have an impact on the result as Long-Bailey is rated first choice by 19% of Labour members who voted Remain, but scores 31% of those who voted Leave.

Starmer is backed as first choice by 34% of Remainers in the survey, but only supported by 17% of Leavers.

The survey was commissioned from YouGov by the Party Members Project, which is funded by the Economic and Social Research Council.