In a poll commissioned by The Times, Yougov found that Corbyn is more popular amongst a sole group of voters split by age - the 18 to 24 year olds.
However, even among this group, the margin of his lead is just two points, with 34 per cent selecting the Labour leader when asked which of the candidates would make a better Prime Minister.
May was chosen by 32 per cent, while 33 per cent were unconvinced by either option.
The figures illustrate Corbyn's difficulties in appealing to voters outside of Labour – within the party, large numbers of young activists back the Islington North MP, but this advantage is dramatically diluted among non-Labour voters.
Overall, May leads with 50 per cent of those surveyed, compared to just 19 per cent for Corbyn.
And while May wins in every other age group, the proportions selecting her over Corbyn increase as voters get older - 40 per cent of 25 to 49 year olds prefer May, but 57 per cent of 50 to 64 year olds say the same.
Among voters of retirement age or older, the Conservative leader's advantage over Corbyn is particularly dramatic.
Just eight per cent of those aged over 65 prefer Corbyn in the Yougov figures, compared to a whopping 72 per cent choosing May.
Even among those who say they plan to vote Labour at the next election, almost 40 per cent either say May would be a better Prime Minister, or say they don't know.
By contrast, 95 per cent of those who plan to vote Conservative say May would make a better Prime Minister, while five per cent say they're unsure. None of those surveyed chose Corbyn.
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