it is often said that the front runner in a tory leadership election never wins
that would be Sunak
the actual election will be performed by the small, mostly elderly, largely anti-EU, largely right-wing membership of the party scattered around the country. The people who chose Johnson.
the few hundred tory MPs will push the choice of only two onto them, usually offering one candidate they think the backwoodsmen will like, and one they think the backwoodsmen will not like. so in reality the MPs control the election and hence the result.
truss is a bit of an idiot but is favoured by the anti-EU Johnson wing
sunak is not favoured and is being attacked by the anti-EU johnson wing
Mordaunt is being attacked by the anti-EU johnson wing
Some might say that being attacked by raving brextremists like david frost should be a badge of honour.