Labour leadership race frontrunner Keir Starmer has vowed to consult party members on electoral reform and include it in a constitutional convention if he becomes the next leader, LabourList can reveal.

The news comes as leadership candidates have responded to questions put to them by the Electoral Reform Society, a political pressure group in favour of replacing the UK’s first-past-the-post voting system with one of proportional representation.

In their responses on political reform, both Keir Starmer and Rebecca Long-Bailey advocated a constitutional convention – as promised in Labour’s 2019 manifesto – and said it would look at a change in the electoral system.

Starmer said: “We’ve got to address the fact that millions of people vote in safe seats and they feel their voice doesn’t count. That’s got to be addressed by electoral reform. We will never get full participation in our electoral system until we do that at every level.”

“I would consult the party membership on electoral reform and include it within the constitutional convention that looks at wider democratic renewal – including abolishing the Lords and furthering devolution on the principles of federalism.”

Long-Bailey noted to the ERS that she has “committed to abolishing the House of Lords, and replacing it with an elected Senate outside London”, and that this new chamber would “be elected with a proportional voting system, and have a codified mandate”.

She added: “But we cannot stop there in seeking to overhaul the deeply undemocratic makeup of the British state. We should also empower a constitutional convention to explore more proportional representation, and really meaningful devolution of power to our local communities, regions and nations.”

Lisa Nandy did not respond to the ERS by the deadline, but at the hustings hosted jointly with Open Labour in January the Wigan MP said “we should trial PR, and we should do it in areas that it doesn’t automatically benefit us”.

Deputy leadership frontrunner Angela Rayner noted her “personal support for moving to STV or preferential voting systems in our internal party elections”, and pledged to “facilitate the debate” around electoral reform.

She also said her “top constitutional priority” would be “scrapping the House of Lords and replacing it with an elected House” in government, while in opposition she has called for Labour to introduce “people’s peerages”.

According to this suggestion put forward by Rayner, Labour would see its nominations to the Lords determined “through our democratic structures rather than simply appointed by the leader”.

Rival candidate Richard Burgon said he would push for Labour to back a change in the electoral system if party members supported it, and reiterated his backing for votes at 16 and abolishing the House of Lords.

Dawn Butler confirmed that she “fully support[s] voting reform”, favours a constitutional convention and highlighted the “need to stop the implementation of unfair boundary changes” as well as mandatory voter ID.

The Brent MP also emphasised that she has “backed calls for a switch to STV for internal elections”, which would make it easier for candidates not included on factional slates to win positions on Labour’s ruling body.

The deputy hopeful added: “I believe our members, for example through party conference, should consider this issue of electoral reform and have their say in deciding our policy for the next election.”

Ian Murray described himself to the ERS as a “long-standing supporter of a constitutional convention” that would “examine House of Lords reform”, and cited his “Labour Campaign for Britain’s Future” proposal.

He added: “As a former councillor in Edinburgh, I campaigned for the introduction of STV for local council elections in Scotland and would strongly support this being introduced in other parts of the UK.”

Labour members, registered supporters and affiliate members have started receiving their ballots. Voting in the contests will end on April 2nd, before the result is announced two days later.