The three major federal parties are gripped in a very tight three-way race, according to overnight polling by Nanos Research for CTV and The Globe and Mail.

The latest numbers for the three leading parties:

Conservatives: 30.8 per cent

NDP: 29.9 per cent

Liberals: 30.9 per cent

Voters were asked: "If a federal election were held today, could you please rank your top two current local voting preferences?"

The results show the three parties in a statistical tie, pollster Nik Nanos told CTV’s Canada AM on Friday.

"This is election is wound up about as tight as it can get," he said. "We’d be tossing coins to find out who would win the election if an election were held today."

However, Nanos said that could change quickly.

While the Liberals and New Democrats have similar levels of support right now, polling shows that many voters would consider switching their support from one party to the other.

The latest numbers show 58 per cent of respondents who said they would rank the Liberals as their first choice, picked the NDP as their second-choice. Out of the respondents who ranked the NDP first, 49 per cent favoured the Liberals second.

"We’re seeing, if I can use the term, political swingers. When we look at the NDP and the Liberal support, there’s a lot of cross-pollination in terms of switching back and forth," Nanos said.

"We could see movement very quickly between New Democrat and Liberal support."

If that happens, Nanos said, it may be enough to propel one of the two parties into the lead.

"The way the Conservatives will lose is if Canadians decide that either Tom Mulcair or Justin Trudeau will be the main challenger," he said.

The daily tracking figures are based on a three-day rolling sample comprising 1,200 interviews. Each evening, 400 eligible voters are interviewed. The tracking is updated each day by adding information from a new day and dropping the oldest day.

The margin of error for a survey of 1,079 decided voters is ±3.0 percentage points, 19 times out of 20.

The Regions:

The Liberals have the highest level of support in Atlantic Canada (44 percentage points) and Ontario (41 percentage points)

The Conservatives are trending up in the Prairie provinces at 55 percentage points, up from 43 percentage points earlier in the week.

The NDP continue to hold a strong lead in Quebec, at 50 percentage points.

Meanwhile, in British Columbia, the race between the major three parties is tightening, with the Conservatives (30 percentage points), Liberals (29 percentage points), and NDP (31 percentage points) all within two percentage points of one another.

Margins of error: B.C.: 7.9 per cent; Prairies: 6.9 per cent; Ontario: 5.5 per cent; Quebec: 6.0 per cent; Atlantic: 9.7 per cent

Poll Methodology:

A national dual-frame (land and cell) random telephone survey is conducted nightly by Nanos Research throughout the campaign using live agents. Each evening a new group of 400 eligible voters are interviewed. The daily tracking figures are based on a three-day rolling sample comprised of 1,200 interviews. To update the tracking a new day of interviewing is added and the oldest day dropped. The margin of error for a survey of 1,200 respondents is ±2.8 percentage points, 19 times out of 20.

Full poll at Nanos Research

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