In an attempt to sweep up the green vote, Liberal leader Justin Trudeau announced this week that if elected, his party will work to legalize marijuana "right away."

Reporters asked him to elaborate on his plan during the leader's announcement on home care in Surrey, British Columbia on Wednesday. Trudeau admitted he did not know yet what rate the drug would be taxed at, or exactly when legalization would kick in — giving a timeline of anywhere from one month to two years.

Trudeau has previously said pot prohibition has resulted in 475,000 people with criminal records since the Conservatives came into power in 2006, and criminalization of the drug costs the justice system $500 million a year. But until now, the Liberal leader has kept relatively quiet on the issue while on the election trail — even when his political adversaries have taken swipes at him with pot jokes.

During a mid-September debate, when Trudeau called the NDP's promises "puffs of smoke," Mulcair jabbed back, "You know a little about that, don't you Justin?" referencing Trudeau's admission long ago that he had smoked weed "maybe five or six times" in his life.

But Mulcair has also said he would make pot a top priority, if elected. The leader of the traditionally left-leaning NDP party has said he would decriminalize pot "the minute we form government."

"The NDP has had the same position for about 40 years," he said in August. "Decriminalizing marijuana is the position of the NDP, it's my position and it's something that we can do immediately."

Legalization of weed would be similar to the legalization of alcohol after prohibition, while decriminalization would mean weed smokers could still be fined for possession over a certain amount, but would not go to prison or have a criminal record for it.

The Conservatives, meanwhile, have said legalizing the drug is a "terrible idea" because it would normalize its use for young people.

Health minister Rona Ambrose told CTV that if legalized, weed would be for sale in corner stores, similarly to how cigarettes are sold.

But in early September, the Liberal leader said corner stores are not "rigorous enough" at checking ID for him to be comfortable with that as an option.

A new CTV poll conducted between Sept. 25 and 27 found Trudeau was not far behind Conservative Prime Minister Stephen Harper, while a poll commissioned by the Toronto Star found the Conservatives are in the lead, with the NDP and Liberals neck-in-neck for second place.