I dont know brit politics as well as Oz politics but in Oz back stabbers dont do well no matter how much the stabee may have deserved it. They are seen as untrustworthy and disloyal.
Evidence suggests there is a lot of back briefing against him by the Boris camp. He is also seen as going against Tory values by raising taxes. I think this leadership campaign could get quite nasty and further alienate the marginal supporters. We'll see.