How Supplementary Votes could influence mayoral election

The Labour Party could benefit most from the return of the Supplementary Votes (SV) system in the Greater Manchester mayoral race, a polling expert has said.

Voters in the region head to the polls on 30 July and will be able to select a first and second choice of candidate as SV comes into replace the first-past-the-post (FPTP) system used at the last election.

A number of candidates have already declared for the contest, triggered after Andy Burnham's successful campaign to become the MP of Makerfield, leaving the post he has held since 2017 vacant.

Prof Jonathan Tonge of the University of Liverpool said Labour could pick up second preference votes from Greens and Lib Dems, while Reform could be less likely to see Restore voters put them as second preference due to "bad blood" between the party leaders.

The system was used in the first two mayoral elections, but was scrapped by the last Conservative government in favour of FPTP system, before it was reintroduced again by Labour.

Under SCV, candidates need to win more than 50% of the vote in the first round to be come mayor or the top two candidates go into a run-off where second preference votes from eliminated candidates are counted.

Experts like Prof Andrew Russell from the University of Liverpool have said the system has both strengths and weaknesses.

"Its greatest strength is that the mayor would be able to claim a mandate from a broader electorate than the FPTP system, when the winner from a multiparty contest might not get more than 25% of the vote," Russell said.

"Its weakness is that it increases the chances of electing someone who's inoffensive rather than anyone's actual first choice."

Paula Keaveney, associate tutor in politics at Edge Hill University, Ormskirk, said second choice votes could be vital and are something candidates will be thinking about.

"If I am a candidate who expects to be in the top two, I need to also have some messages for those who won't vote for me first, but might put me second.

"For example, if I am Labour, I might want to have some messages for Lib Dems. I certainly don't want to annoy them. If I am Reform, I might want to have some messages for Conservatives.

"In first-past-the-post, if the lead and main challenger are clear, both can say vote for me to stop the other, however in SV, voters have the ability to vote with their hearts in the first choice and then their tactical heads in the second."

Keaveney said SV "only really helps parties that have a decent chance of being in the top two".

"If the Greens are not in the top two, it doesn't matter how many second choice votes they received."

Prof Tonge said he sees the second vote as crucial because in the most recent council elections across Greater Manchester "no party came close to winning 50% of the vote; Reform led on 31%, followed by Labour on 24% and the Greens on 19%".

He said it was not possible to predict how votes could be transferred as "none of the three previous mayoral contests in Greater Manchester has ever gone to round two."

Tonge said Reform would have been favourites if the voting system remained first-past-the-post, but not with SV.

"Some transfers to Reform's candidate, Sian Astley, may come from the Conservatives, distant runners-up last time but trailing in the one opinion poll to date.

"Bad blood between the leaders of Reform and Restore Britain, Nigel Farage and Rupert Lowe, evident in the recent Makerfield by-election, may prevent many Restore voters offering second preferences to Reform."

He said in contrast Labour's Bev Craig is a "potential recipient of a wider range of transfers, from Greens and Liberal Democrats most probably, which may get her over the line".

Tonge added: "The Greens have tried to claim this is a contest between them and Reform – which given Labour's historical strength across Greater Manchester and possible Burnham fillip – is clearly not the case.

"However, the party's candidate, Geraldine Coggins, may do very well with transfers from other party supporters – if – big if – she can survive into the second round."

All the candidates standing in the by-election will be announced at 16:00 BST on Monday.

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