The Liberals have a narrow three-and-a-half point lead over the Conservatives nationally but have opened up a sizeable advantage in Ontario, a new poll has found.

Mainstreet Research polled 1,876 Canadians over the weekend and found that Justin Trudeau’s Liberal party has the support of 37.5 per cent of decided and leaning voters compared to 34 per cent for Andrew Scheer’s Conservative party. The Green party were in third with the support of 10.8 per cent of decided or leaning voters while the NDP were in fourth (8.4 per cent) and the People’s Party were in fifth (4.6 per cent). The Bloc Quebecois, meanwhile, had the support of 15.5 per cent of voters in Quebec.

In Ontario, the Liberals had the support of 45.3 per cent of decided or leaning voters compared to 30.4 per cent for the Conservatives, 10.1 per cent for the Greens and 7.5 per cent for the NDP.

The Liberals also performed well in Atlantic Canada (49.1 per cent) and Quebec (40.3 per cent). The Conservatives, meanwhile, were the top choice in Alberta (63 per cent) and the Prairies (50.8 per cent).

“This is bad news for Andrew Scheer and the Conservatives as the Liberals have crossed the 40 per cent mark in Atlantic Canada, Quebec, and Ontario,” Mainstreet Research President and CEO Quito Maggi said in a press release. “If the election were held today, the Liberals would comfortably win a majority. The solace for the other parties is that the election is not going to be held today and that they will have the entire writ period to chip into the Liberal lead.”

While the Liberals appear to be off to an early lead ahead of the official start of the federal campaign, the Mainstreet Research poll found that there was some room for improvement for Andrew Scheer’s Conservative party.

A total of 11.1 per cent of all respondents said that they remain undecided.

The poll is considered accurate to within 2.26 percentage times, 19 times out of 20.