With MPs headed back to work Monday as Parliament resumes, signs of an unofficial launch to the next federal election campaign are beginning to show.

There is still over one year to go before the October 2015 fixed election date, but parties are already revving into campaign mode.

In interviews on CTV's Question Period on Sunday, both Liberal leader Justin Trudeau, who is currently leading in the polls, and NDP leader Thomas Mulcair, who is third behind Stephen Harper’s Conservatives, made reference to the approaching election.

Trudeau brushed off Conservative and NDP criticism that he is too inexperienced to run a country, repeating that he’d rather focus on the needs of Canadians than personal attacks. He also defended himself against critics who say his party lacks solid plans or policy.

"We’ve been talking about our ideas for two years now, whether it’s around pipelines we support, whether it’s around trade deals we think are going to be good for the middle class," Trudeau told CTV’s Ottawa Bureau Chief Robert Fife.

"The fact of the matter is we still have a long way to go until the next election and I’m making sure that Canadians have a full possibility to input and shape the kinds of solutions that we’re going to need to grow this economy."

In contrast, the NDP has already revealed a number of policies that will make up part of the party’s election platform, including a federal minimum wage policy, which Mulcair announced Saturday.

The NDP has also rolled out a new election slogan, "Change that’s ready," and an offensive on Trudeau that mimics Conservative claims that the Liberal leader is inexperienced.

"I think the most important thing for the NDP to accomplish in the coming year is to show Canadians that we are indeed a government in waiting," Mulcair told CTV’s Question Period. "We’ve never been in a stronger position heading into an election year."

Mulcair also reiterated his past comments that Trudeau is "not ready" to lead the country, accusing the Liberal party of feigning progressive intentions to get elected. "Look at what they’ve done every time they’ve been in power. They always flash left to get elected but then they turn right once they get elected."

Trudeau and Mulcair also took the opportunity to criticize some of the current Prime Minister’s policies.

Trudeau said a recent interview in which former prime minister Brian Mulroney criticized Harper is proof that "progressive" Conservatives have grown tired of Harper, who is in his third term in power.

Mulcair alluded to the Conservatives’ recent problems with the Supreme Court of Canada, saying: "Every time Stephen Harper has complained about something and gone to a real court, he’s lost."

Over the past year, the Harper government has had to rejig plans related to Senate reform, its "tough on crime" agenda and Canada’s anti-prostitution laws after the Supreme Court weighed in. Harper and Justice Minister Peter MacKay also had a public dispute with Chief Justice Beverly McLachlin earlier this year related to the proposed appointment of Federal Court Judge Marc Nadon to the country’s top court.

For the Conservatives, the key to a fourth-straight term in power may lie in a projected federal surplus of about $10 billion. The money could enable a 2015 budget that includes tax cuts and spending to woo voters.

On Thursday, Finance Minister Joe Oliver announced that the Conservatives would use some of the surplus money to cut Employment Insurance premiums for small businesses. Oliver said the initiative, which has been popular with business leaders, will create jobs and economic growth.

The government is also launching pre-budget hearings this fall to give people and groups a chance to voice feedback ahead of the 2015 budget.

Other things to watch as parliament returns

Beyond the first stirrings of campaign fever, there are a few other stories to watch in the upcoming House of Commons session.

Both the NDP and Liberals have called for more discussion on Canada’s role in Iraq after Harper announced the deployment of about 100 Canadian special ops forces to advise Kurdish fighters. And the Liberals are calling for a hearings on Canadians who have gone abroad to fight with extremists groups and then returned to Canada.

There are also controversial bills on cyberbullying and prostitution still making their way through the House.

The government has said that Bill C-36 would protect sex workers and that Bill C-13 would make it a crime to distribute intimate images without consent. But “Canada’s most famous dominatrix,” Terri-Jean Bedford, said the prostitution bill endangers sex workers, and Canada’s privacy commissioner warned that the cyberbullying bill may give police power to invade Canadians’ online privacy.

For more Canadian politics, watch CTV’s Question Period on Sundays at 11 a.m. EDT.