My big concern is that brexit has become a totem for so many they will simply disregard the huge amount of suffering johnson will cause as long as he's pro brexit, it's a ridiculous attitude to have but it definitely exists
He's a vacilator though. He's not like an ERGer and potential candidate, Steve Baker, who has been a straight arrow on this issue of Brexit. Johnson was never known for strong views on leaving Europe prior to the referendum; then he became an arch-leaver; then he caved in for May's 3rd attempt at passing her withdrawal plan (which would have shut down a no deal Brexit); now he's for a no deal Brexit if no agreement by October 31st.
People wont be allowed to forget that. The LP will play on that inconsistency and pose the question when the next u-turn will be (on Brexit and other matters).
He's flakey, and people sense flakiness and dont place their faith in anyone with the faintest whiff of it about them.