Don't be so sure.
Boris is hated by most of his own MPs. A lot of them are jumping on his bandwagon now, for two reasons. 1) He's popular amongst the general public, and might just save the Conservative Party from defeat in a general election. And 2) He's extremely popular amongst the Tory members, and so was always going to win. So if you are a Tory MP and want a position in the cabinet in 6 months time, vote Boris now.
He's doing well because he's popular. He's popular because he's doing well.
But as we all know, he's a buffoon. He's narcissistic, iditioc, and prone to pie in the sky thinking. His list of achievements as London Mayor or Foreign Secretary are essentially zero. He doesn't like to be told no, and he's going to immediately be clashing with the EU and possibly the civil service.
As soon as the polls start turning against him, he will leach support. As soon as he starts putting his foot into his mouth, the public will turn on him.
And he's got the exact problem Theresa May had. Either jam no-deal through a Parliament that doesn't want no deal, or jam "the deal" through a Parliament that doesn't want "the deal".
If we are still in the EU come 1st January 2020, I think a second referendum is inevitable.