[bluehatbrit]

It's also worth noting that he's being investigated by the Parliamentary Standards Committee. Now that he has stepped down as an MP, that investigation would ordinarily be paused (and is from what I can tell). It would be resumed if he won but he gets a while to organise things before he has to face them again.

[manarth]

And if the Standards Committee find sufficient wrong-doing to suspend an MP for 10 days or more, the suspension automatically triggers a recall-petition.

If the recall-petition is signed by 10% or more of voters in that MP's constituency, this triggers a by-election.

So there's a reasonable possibility that once the investigation concludes, there will be another by-election in Clacton.