Despite getting knocked down to third-party status, Tom Mulcair gave no signal that the NDP’s "next chapter" would begin without him.

Speaking to supporters at NDP headquarters in Quebec, Mulcair promised to take a stand on important issues such as climate change, health care and Canada's First Nations.

"I want you to know that we will work for you each and every day in this new majority Parliament," said Mulcair.

It's been a rollercoaster campaign for Mulcair and the NDP, but it’s mostly been downhill.

When the writ dropped on Aug. 2, his party was leading in the polls and looked poised to end Stephen Harper's nearly 10-year reign.

But over the course of one of the longest election campaigns in history, the NDP experienced a reversal of fortunes, and tumbled all the way down to third place.

Liberal Leader Justin Trudeau has replaced Mulcair as the choice of voters who wished to oust Harper from 24 Sussex Drive.

In his concession speech, Mulcair said he had congratulated his opponents, including Trudeau for his "exceptional achievement."

However, Mulcair promised to grind it out in Parliament for those who had voted for his party.

"With this election Canadians have asked to us all work for them," said Mulcair. "We will not let them down."

"As a party with established roots in all corners of this country and deep roots right here in Quebec, the next chapter begins in effort to build a better Canada."

In Toronto, which was thought to be a battleground for all three parties, victorious Liberal MPs painted the city red.

And Olivia Chow, the wife of the late Jack Layton, was one of the NDP candidates who failed to capture a seat for the party.

Chow was matched up in the hotly contested downtown Toronto riding of Spadina-Fort York against Liberal Adam Vaughan.

Despite the loss, an emotional Chow remained optimistic about the future.

"We pick ourselves up from our highs and lows together," she told supporters.

"Never ever let them tell you that it can't be done."

While the NDP led early in the 78-day campaign, that lead quickly evaporated in the final month.

Heading into September, the party was significantly ahead of the Liberals and Conservatives at polls.

But on August 25, Mulcair announced that the party could finance all of its promises on a balanced budget.

The move corresponded with a dip in the polls that moved the other two major parties within striking distance.

While both the Liberals and NDP promised increased spending if elected, Trudeau conceded that his party would run small deficits.

The decision for the left-leaning party to shift to the centre seemed at odds with its past leadership.

Brian Topp, the runner-up to the party's 2012 leadership vote, predicted that such a move could prove disastrous.

"I don't think that we will succeed if we do that," said Topp at the time.

"If there are two parties pitching Liberal ideas in the next election, voters will choose the real one."

The NDP's support also seemed to take a hit at the French-language debates.

The party had won 58 of Quebec's 75 seats, during the late Jack Layton's "Orange Crush" surge in the 2011 election.

And Mulcair, who had previously served as the Environment Minister for Quebec’s Liberal government, was favoured to repeat those results.

At the debate, the niqab took centre stage as Bloc Quebecois Leader Gills Duceppe and Harper called for a ban on the garment during citizenship ceremonies.

Despite the fact that the proposal on the face covering was popular in Quebec, Mulcair backed the current rules that only require that they are removed for identification purposes, but not during the swearing-in process.

Following Mulcair's stand, the party once again sagged in the polls.

On September 24, the day of the debate, the NDP, Liberals and Conservatives were polling within a percentage point of each other according to Nanos Research.

Four days later, the NDP had fallen to 27.6 per cent, while the Liberals and Conservatives held strong at 32.5 and 31.5 per cent respectively.

And the party never recovered, trailing the other two parties for the rest of the campaign.

But even on its final weekend, Mulcair insisted he was in a position to form a government.

"We're going to get it done," said Mulcair at rally in the Toronto riding of University-Rosedale on Sunday.