Proposals to require voters to show ID before voting have been criticised by campaigners who believe it will give an advantage to the Tories.
Labour had argued that the plans “disproportionately” discriminate against ethnic minorities, and working class voters who were less likely to Conservative.
Jeremy Corbyn said it was a chance to “rig the result of the next general election” and would “suppress voters”.
“The people that the Tories are trying to stop voting will be disproportionately from ethnic minority backgrounds, and they will disproportionately be working class voters of all ethnicities,” he said.
It follows the party’s research which claims there was only one conviction out of 28 allegations of in-person voter fraud in 2017, after a total of 44 million votes were cast.
They added 3.5 million UK citizens do not have access to any photo ID, with 11 million lacking a passport or driving licence.
But pollsters have now pointed out the measure would also significantly impact Leave voters in any second Brexit referendum.
Research carried out after the EU referendum found that areas where large numbers of people do not hold a passport leaned mostly towards Leave.
New analysis by Joe Twyman from Deltapoll found the correlation more notable with Brexit voters than with those who voted Conservative or Labour.
Separately Mike Smithston from Political Betting noted that those less likely to have a drivers’ license are the oldest in society, who are often more likely to turn out to vote, and are some of the biggest age brackets to have voted to Leave.
In a report from the Electoral Reform Society, following a 2018 trial, warned of the consequences on the poorest in society.
They said: “It would hit the already marginalised hardest: poorer C2DE social grade voters were half as likely to say they were aware of the ID requirements before the trials this May.”
A Cabinet Office spokesman said the system was about restoring “public confidence” in elections.
They said: “Showing ID to vote is a reasonable and proportionate way to protect our elections – it is something people already do in everyday life and voters in Northern Ireland have been doing it with ease for decades.
“Voter ID is one part of a body of work this government is delivering to give the public confidence that our elections are secure and fit for the 21st century.”