Mad Max is the leading contender and Andrew Scheer is considered a strong candidate. That says it all.

A guy whose main claim to fame after 10 years in power is leaving sensitive documents at his girlfriend's house (and who fancies himself as a so called "Libertarian" who sat silently while his leader interfered in our capital markets, introduced measurements giving the Govt more powers to spy on its citizens, etc...) and in Scheer: a totally ineffectual Speaker of the House who jumped on command whenever Harper looked his way.

They did a great job of concealing their "leadership" qualities for a decade.

O'Toole is too new to be permanently stained by the CPC "legacy" and Chong is the only remaining long term CPC MP who ever had the backbone and guts to say "no" to Harper.