The Conservatives are heading for a potentially catastrophic defeat in the Wakefield byelection amid reports Boris Johnson could face a vote on his future next week, according to a new poll.
A survey by JL Partners and reported in the Sunday Times gives Labour a 20-point lead over the Tories in the Yorkshire constituency.
The poll puts Labour on 48% and the Tories on 28%, down by 19 points.
The prime minister secured his majority of about 80…