A poll carried out before the European elections in May found thatjust 7% of no-deal supporters intended to vote Tory.
The huge shift comes at the expense of the Brexit Party, who now only have the support of 11% of no-dealers, compared to the 80% they had in May.
The figures come as four Brexit Party MEPs quit and announced they would be supporting the Tories and Mr Johnson’s Brexit deal, urging their own voters to do the same.
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The YouGov poll also had more good news for the Tories, as it showed that 83% of those who favoured a deal would be voting for them - meaning they have majority support from no-deal supporters, as well as those who either support the current deal or a future alternative deal.
The figures will make pleasing reading for the Prime Minister, who has been keen to shape December’s vote into the ‘Brexit election’.
However, there is also good news for Labour as the expected Remainer drift to the Lib Dems has not happened.
Some 49% of those surveyed who support staying in the EU are now planning to vote Labour, compared to 30% for the Lib Dems.