Labour and the SNP stand to gain in the North-east from changes to the system of voting for Westminster elections, it has been claimed.
The Electoral Reform Society (ERS), which says the current first past the post method is “failing”, simulated the June 8 General Election having replaced first past the post (FPTP) with the single transferable vote (STV) system.
Aberdeen, Aberdeenshire, Angus and Dundee have eight MPs; curently five are Conservative and three SNP.
A new ERS report says that if STV had been used, there would be three MPs apiece for the Tories and SNP, while Labour would have two.
The ERS was unable to predict which constituencies would change hands under the simulation due to the method it had used.
ERS chief executive Darren Hughes said: “Our report shows how, far from being ‘strong and stable’, FPTP is failing to deliver for the public.
“In the end, we have a system that recognises the geographical location of a voter and nothing else. It is where voters are – rather than their choices – that matters.”
Ross Thomson, the Conservative MP for Aberdeen South, said: “While voting systems such as STV have worked well in Scotland, FPTP is well-established and is easily understood by the electorate.
“In the 2011 referendum the British people chose to keep FPTP for Westminster elections and it’s only right that we respect that result.”
Shadow Scottish Secretary Lesley Laird MP, of Labour, said: “This report highlights the huge number of marginal seats in Scotland.
“It is now clear Scotland holds the key to a Labour government and that is why Jeremy Corbyn will be bringing our message of hope and optimism to Scotland this week.”
Mr Corbyn is due to visit the Western Isles and the Central Belt.
An SNP spokesman said: “The SNP has been a long-standing supporter of electoral reform – and our 2017 manifesto called for FPTP to be replaced by a proportional system.”