Toronto, Aug 7 (IANS): Four Canadian politicians went head-to-head in Toronto as they faced off in their first debate of the federal election in October.

Conservative Prime Minister Stephen Harper, New Democratic Party (NDP) leader Thomas Mulcair, Liberal leader Justin Trudeau and Green Party leader Elizabeth May took part in the debate, hosted by Canadian national magazine Maclean's and moderated by its political editor Paul Wells.

The two-hour debate focused on national issues including economy, energy, environment, foreign policy and security.

On August 2, Harper said he has officially asked Canadian Governor General David Johnston to dissolve the parliament, kicking off an 11-week campaign ahead of the country's 42nd election slated for October 19.

After the announcement, Canadian opposition leaders blasted Harper's record in office, accusing him of poor economic management and of ignoring the plight of jobless and middle-class Canadians who have seen their incomes stagnant.

Stretching over 78 days, this year's campaign will be the longest federal campaign since 1872. Its result will set the country on a course that either solidifies a decade of change under Harper's Conservative Party on everything from taxes to foreign policy, or rejects the ideology behind those policies and embraces a more progressive approach promised by the NDP and the Liberal Party.

With this election, the House of Commons is being increased to 338 seats from 308, which means Harper must win at least 170 seats to form a majority government.

Other debates have been planned following the first one in Toronto.

The Globe and Mail newspaper is organising one for September 17. The Munk Debates, a semi-annual series of debates on major policy issues held in Toronto, is planning a leaders' exchange on foreign policy.