But compared to the ferocious pit-bull attacks the Tories unleashed against past Liberal leaders, the latest effort is more like an attack puppy.
The ruling party has uploaded two free ads on YouTube, one English, one French, apparently content to rely on mainstream and social media to spread the word.
The ads come three months after Mulcair was chosen to lead the NDP — a crucial lag time in which Mulcair has managed to boost his party into a slim lead over the Tories in opinion polls and burnish his own credentials as a would-be prime minister.
By contrast, the Tories gave Stephane Dion and Michael Ignatieff virtually no time to introduce themselves on their own terms to Canadians when they were elected to lead the Liberals.
The Tories mounted immediate, expensive, prime-time television advertisements that denigrated Dion and Ignatieff, respectively, as "not a leader" and "just visiting."
The Conservatives refuse to say whether they eventually intend to pay to broadcast the relatively tame anti-Mulcair ads on TV.
The delay in going after the NDP leader suggests the Tories have no interest in demolishing Mulcair as thoroughly as they did Dion and Ignatieff. Indeed, Prime Minister Stephen Harper's reputed long-term goal of obliterating the Liberals depends on the NDP continuing to consolidate support among centre-left voters.
Nevertheless, with the NDP now edging into the lead in polls, the Tories appear to have decided it's time to take some air out of Mulcair's honeymoon balloon.
The English YouTube ad accuses the NDP of indulging in "risky theories, dangerous economic experiments" such as supporting imposition of a carbon tax "that will raise the price of everything including gas, groceries and hydro."
It concludes with the tag line: "We can't afford Mulcair's NDP."
The French ad pushes a similar message but contrasts Mulcair's carbon tax agenda with Harper's record of job creation.
In fact, Mulcair advocates putting a price on carbon through implementation of a cap and trade system — a model favoured by the Harper government itself until recently.