The Conservatives will really, really have to screw up to lose the next election.
However, if you know anything about Canadian federal politics, the federal Tories have been in the past more than adept enough at doing so.
The people who want Harper out bad must understand that they are fighting history. The Liberals are the natural governing party, but they are not the only governing party. And when the Canadian public gets tired of the Liberals, they spank them and send them to the corner for a term or two before they allow them back to govern.
And the beneficiary of this are the Conservatives.
Its a natural reflex in Canadian politics.