Image copyright Reuters/AP Image caption Stephen Harper, Tom Mulcair and Justin Trudeau turned out in their constituencies on Monday morning

Canadians have voted in parliamentary elections that could bring the first new leader in nearly 10 years.

Incumbent Conservative PM Stephen Harper is fighting for a rare fourth term but the frontrunner is Liberal leader Justin Trudeau.

Early counts in the eastern provinces show the Liberals ahead in all 32 seat races there.

Mr Trudeau is now poised to form the next government, Canada's CBC and CTV networks predict.

They say it is still unclear whether it will be a majority or minority government.

As the first results from Atlantic Canada began pouring in, former Conservative Justice Minister Peter MacKay said: "A sea of change here. We are used to high tides in Atlantic Canada. This is not what we hoped for."

The Liberal Party was always expected to perform well in the region.

The Conservatives are now in danger of losing all 13 seats they held in Atlantic Canada in 2011.

A third party, the left-leaning New Democratic Party (NDP), could also play a decisive role in whether Mr Harper and his Conservatives lose power.

Late surge

Voting hours were staggered across the country and polls opened in Newfoundland at 08:30 local time (11:00 GMT). Polls closed in the west of the country at 19:00 (02:00 GMT).

It is one of the longest and possibly closest election campaigns in Canada's history, with leaders criss-crossing the country to try to sway undecided voters.

To form a majority government, a party needs 170 seats in the 338-member parliament.

Canada votes: live updates

Mr Harper, 56, is selling himself as the steady hand who can steer Canada's troubled economy back on track.

His campaign has run TV advertisements saying that Liberal leader Mr Trudeau, 43, is "just not ready" to take office.

Image copyright AP Image caption Queues were reported at some polling stations

Image copyright AP Image caption Justin Trudeau, seen here at the head of the human pyramid, started the campaign in third place

"Every single vote for a Conservative candidate is a vote to protect our economy against Liberal and NDP deficits and taxes," Mr Harper told supporters in Regina, Saskatchewan, on Sunday.

As polls opened, he tweeted that a vote for the Conservatives would "protect Canadian jobs and our economy".

Mr Trudeau started the race in third place but the Liberals took the lead in opinion polls in a late surge.

Stephen Harper's final stand?

At the scene - Rajini Vaidyanathan, BBC News, Toronto

The Toronto Blue Jays have their first home game in the playoffs for baseball's American League Championship series, and a sea of fans wearing blue T-shirts are filling downtown Toronto ahead of the big game.

But will blue be the dominant colour for the other big result of the night? After nearly a decade in power, the Conservatives (the blue team in this political race) are fighting to stay in office.

The Liberals (red) led by the photogenic Justin Trudeau have been ahead in the polls. If they win it'll be a stunning victory for a party which began this race in third.

If Mr Harper hangs on, he'll pull off an equally impressive feat in becoming the first prime minister to win a fourth term in more than a century. Either way this election will be historic. Will Canadians plump for continuity or change?

Speaking in Calgary, Alberta, on Sunday, Mr Trudeau urged voters to "come together as a country".

Mr Trudeau's father, Pierre, is considered the father of modern Canada.

Image copyright Reuters Image caption Tom Mulcair, with wife Catherine, addressed supporters in Montreal on Sunday

Media playback is unsupported on your device Media caption In five words: How you feel about Canada

NDP leader Tom Mulcair, 60, is hoping to build on his party's second-place finish in the 2011 elections.

However, support for the NDP appeared to have fallen in recent weeks.

At a stop in Toronto, Mr Mulcair hit out at the Liberal leader, saying: "They may try to fool you by giving the old car a fresh coat of paint. But as we've seen, the Liberal Party is just as rusted-out underneath as it was when Canadians kicked them out of office for corruption the last time."