Anniebach, Jeremy Corbyn and the Labour Party were more than twenty points behind in the opinion polls at the start of the 2017 general election campaign. The foregoing was the sole reason why Theresa May called that disastrous election for her party as it was her intention to destroy the Labour Party.
Well, all her present problems and that of the Tory party can be linked back to the result of that election and the Labour Parties far better than expected performance in it.
The above is the reason why Jeremy Corbyn wishes to have a general election rather than a second peoples vote on Brexit. In that, it has been demonstrated that when people see the compleat labour policies on such matters as Housing, the NHS, the Gig Economy, workers right and much more, they are then prepared to support them.