In response to scuttlebutt on a website he called a press conference and with his wife at his side admitted "inappropriate interactions" with the press secretary, who promptly and publicly declared there had been no interest on her part. It was the final straw for former deputy leader Christine Rankin, who called the press conference "excruciating and embarrassing" and resigned from the party's board.
Within two days most of the board had gone. Mr Craig was left with a party to himself, which is what it always looked like. He financed it and he alone fronted it until one or two luminaries such as Ms Rankin joined him for the election. Many would have been surprised that until this week it still had a functioning board.
Mr Craig was, or is, one of those lone wealthy figures found in many democracies who aspire to public office on their own terms but with no particular mission to accomplish. His signature policy at last year's election was to let the public decide most questions at referendums. Early on he would rule out no proposition put to him, even a couple that were plain wacky.
He was an amateur with enough self belief to stand up to interviewers' scorn and attacks from Winston Peters, another lone figure who aspires to office on his own terms with no particular mission in view. They both thought they were trawling for the same votes and New Zealand First is expected to gain from the Conservatives' demise now.
But that should not be assumed. Mr Peters and Mr Craig were starkly different characters, one forever evasive about his post-election intentions, the other frank and definite. Artless candour is a political attribute until there is something personal to hide. Mr Craig had much to hide this week and he kept the details to himself awkwardly, self-servingly and unfairly to the woman (not) involved.
Politics needs new blood in its contests and Mr Craig supplied some. But his run is over. He returns to obscurity leaving others to wonder what he ever meant to achieve.