The Liberals have maintained a razor-thin lead over the Conservatives across the country, while also opening up substantial leads in Ontario and Quebec in a week that threatened to plunge Canada into a summer election, according to a new poll from EKOS released exclusively to CBC News.

Asked which party they would support if a federal election were held tomorrow, 33.7 per cent of respondents opted for Michael Ignatieff's Liberals, while 32.4 per cent chose Stephen Harper's Conservatives, EKOS said.

The Liberal numbers are a drop from the 35 per cent support reported in a similar EKOS poll conducted last week.

About 16.3 per cent supported the NDP, while the Green party was the choice of nine per cent and the Bloc Québécois was backed by 8.4 per cent.

The survey was conducted between June 10 and June 16 and involved a random sample of 3,422 Canadians, using Interactive Voice Recognition (IVR) technology, which according to EKOS "allows respondents to enter their preferences by punching the keypad on their phone, rather than telling them to an operator."

It has a margin of error of plus or minus 1.7 percentage points, 19 times out of 20.

The polling window ended before Ignatieff and Harper announced Wednesday they had reached a deal to form a study panel to examine employment insurance over the summer in exchange for the Liberals' support of the minority Conservative government in a House vote on Friday.

Despite the week's political brinkmanship, both leaders insisted they didn't want to trigger an election, which EKOS president Frank Graves said was on the mark in terms of gauging Canadians' lack of appetite for a summer vote.

Weekly tracking between June 10-16. Graves said the poll figures favour the Liberals, particularly in the seat-rich provinces of Ontario and Quebec, while the Tories remain strong in the West.

But Graves said the numbers were far from assuring a Liberal victory, while a majority government looks like a "distant hope" for both parties.

“An election would be a risky bet for both of them,” he said. ”It would be a crapshoot right now over who would win."

Canadians' outlook on economy looking up, poll suggests

Graves added the poll suggests Canadians are getting more optimistic about the economy, a factor that may favour the Conservatives.

About 40 per cent said they feel better about the economy than they did three months ago, a three-percentage point boost from the previous week.

Some 47 per cent of respondents disapproved of Harper's job performance, compared to 33 per cent of respondents who approved.

Ignatieff's own job performance ratings, Graves said, appear to have stalled and may be backsliding, with 32 per cent of respondents approving and 34 per cent disapproving.

He said the numbers suggest the public is "not all that impressed" with either leader at this point.