Tom Mulcair took aim at the Conservatives鈥� economic policies as he launched his election campaign Sunday, promising to bring change to the federal government.

He said Prime Minister Stephen Harper鈥檚 early election call, which triggered a 78-day campaign, is an unnecessary burden on taxpayers.

鈥淚 believe that governing is about priorities," the NDP leader said at his campaign launch in Gatineau, Que. 鈥淢r. Harper's priority is to spend millions of dollars on self-serving government advertising and an early election call.鈥�

Mulcair began his speech by taking aim at Harper鈥檚 economic policy, which has recently come under fire following a five-month slump in the Canadian economy.

鈥淚鈥檝e heard the calls for change grow louder and it isn鈥檛 difficult to see why,鈥� Mulcair said. 鈥淲ages are falling, incomes are stagnant and household debt is skyrocketing. Middle-class families are working harder than ever but can't get ahead.

鈥淐learly, Mr. Harper, your plan is not working.鈥�

Mulcair then accused the Conservatives of gutting Canada鈥檚 climate protection laws and damaging the country鈥檚 reputation as a leader in environmental action.

"My priority is to strengthen and enforce environment rules here at home and have Canada do its part in tackling climate change on the world stage," he said. 鈥淵ou can鈥檛 make a choice between environment and economy. You have to do them both together.鈥�

Mulcair, who has made 鈥渃hange in Ottawa鈥� the catch phrase of his campaign, is currently tied for first place in the polls.

CTV鈥檚 July 31 poll showed the Tories are the top choice for 31.5 per cent of survey respondents. New Democrats followed closely behind at 30.1 per cent, while Trudeau鈥檚 Liberals were in third, with 29 per cent. That means all three parties have a good shot at forming Canada鈥檚 next federal government in October.

Mulcair also promised to bring openness and transparency to federal politics in contrast to a Conservative government plagued by accusations of wrongdoing.

He was also the only party leader to talk about First Nations during an opening campaign speech.

鈥淢r. Harper's priority has been to spend $100 million a year fighting First Nations, Inuit and Métis peoples in court,鈥� Mulcair said. 鈥淢y priority is to build a respectful nation-to-nation relationship with our first peoples that recognizes inherent rights and brings us closer to reconciliation.鈥�

Despite a lengthy attack on Harper, Mulcair made no mention of Justin Trudeau and the Liberals during Sunday鈥檚 campaign event. Instead, Mulcair spoke of himself as the only credible alternative to the Conservatives.

Earlier this week, Mulcair further alienated Trudeau from the election campaign by announcing that he would not participate in any debates that didn鈥檛 include Harper.

鈥淚n this election campaign, Canadians have a clear choice,鈥� he said. 鈥淔our more years of Mr. Harper and the Conservatives or my plan for change.鈥�

According to a recent CTV poll, 66 per cent of Canadians want a change of government.

Voters now have 78 days to decide who they want in power before heading to the polls on Oct. 19.

The 11-week election period will be the second-longest in Canadian history.