– Prime Minister Stephen Harper sought to shore up support against front-running rival Justin Trudeau in battleground Ontario as Canada's election campaign entered its final week.

Harper, hoping to become the first leader in more than a century to win a fourth straight term, must win several key districts in the nation's most populous province in order to prevent losing power to the surging Liberal Party. The latest polls show Trudeau's team has taken a clear lead, breaking a ­weekslong deadlock.

Harper is spending the next few days in suburban Toronto and southwestern Ontario cities such as Kitchener, a region to which he owes his rise to power and where data suggest the Conservatives are vulnerable. To counter Trudeau's gathering momentum, the Conservatives have started warning Canadians what might happen if he wins.

"The choice we make next Monday will have real consequences and the wrong decisions in Ottawa on taxes, on spending, on deficits will have real consequences for families, for seniors, for all Canadians everywhere," Harper said at an event in Waterloo, Ontario. "That's why, for our Conservative Party, protecting our economy is our number one ­priority."

Trudeau's Liberals now lead with 36 percent of the vote, polling by Nanos Research for CTV and the Globe and Mail released Monday shows. Harper's Conservatives are at 29 percent and Tom Mulcair's New Democratic Party (NDP) sits at 24 percent, Nanos found. Trudeau has in particular built a lead in vote-rich Ontario, where he stands at 45 percent, followed by 33 percent for the Conservatives and 18 percent for the New Democrats.

The polls suggest no party will have enough support to win a majority in Parliament and any government will require the support of other parties to stay in power.

A minority Liberal government is the most probable outcome, a result that could weaken the country's currency in part because of Trudeau's possible reliance on the labor-friendly NDP to govern, the Canadian unit of Macquarie Group Ltd. said.

Trudeau kicked off his week with a family visit to a pumpkin patch just outside Ottawa on Monday, a Thanksgiving holiday in Canada.

Trudeau, the son of former Prime Minister Pierre Trudeau, has taken aim at the Conservatives in recent days, and did so again Monday.

"We don't need to convince them to leave the Conservative Party. We need to show them how Stephen Harper's party has left them," Trudeau said.

The Conservatives have been weighed down by a sluggish economy, as well as controversies including a Senate spending scandal and Harper's response to the Syrian refugee crisis. Trudeau, whose Liberals governed from 1993 until 2006, is the only leader proposing deficit spending, in part to fund an infrastructure blitz aimed at spurring growth.