Fifty-three per cent of adults quizzed in the survey by polling firm ORB supported the way the Prime Minister is preparing the way for the country's departure from the European bloc.
In a significant boost, it was the first time the regular poll has shown a majority backing Mrs May's approach since she took over in Downing Street last July.
The figure – which follows the Prime Minister's keynote speech on her Brexit principles last month – was up from 38 per cent per cent in January.
Fifty-three per cent of adults polled supported the way the Prime Minister is preparing for brexit
It was the first time the regular poll has shown a majority backing Mrs May's approach
Polling data gathered by ORB also revealed rising confidence in Mrs May's prospects of agreeing a beneficial deal for the country with the EU.
Last month, 35 per cent of voters expected the Prime Minister to get the "right deal" but the figure increased to 47 per cent this month.
Half of voters (50 per cent) felt the country will be better off outside the EU, up from 44 per cent last month.
70 of voters felt the Government will have more control over immigration after leaving the bloc
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Continued cooperation with the EU to tackle terrorism and international crime.
And 70 of voters felt the Government will have more control over immigration after leaving the bloc, up from 59 per cent last month.
The ORB poll found that voters aged under 34 were most likely to be sceptical about the benefits of leaving the EU.
ORB interviewed a sample of 2,058 adults online across the country between the 3rd and 5th February 2017.