In a survey carried out for the Times, the pollster quizzed almost 400 people who voted Labour in 2015, and found that 31 per cent of picked May when asked which of the two party leaders would make the best Prime Minister.
Corbyn was named by only a marginally larger group of the 2015 Labour voters at 36 per cent.
Of the total polled by Yougov, 52 per cent opted for May, and just 18 per cent chose the Labour leader.
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However, the pollsters' figures also found a slight dip in broader support for the Conservatives.
Asked which party they would back in a general election tomorrow, 34 per cent cited May's party, down four per cent from the last set of figures.
And despite the lack of faith in Corbyn personally, the majority of that loss was to the benefit of Labour, which saw a three per cent increase to 31 per cent.
Ukip also saw a small rise in popularity.
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The figures also handed former Prime Minister David Cameron a small fillip – more people rate the now Witney MP as a good or great leader than any of his predecessors since Margaret Thatcher.
Thirty-two per cent supported Cameron, and even though 34 per cent described him as poor or terrible, the most recent PM's tenure is regarded more favourably than that of Gordon Brown, Tony Blair or John Major.
However, support for all five is dwarfed by that for the Iron Lady – 43 per cent described Thatcher as either a good or great Prime Minister.