Liberal Leader Justin Trudeau says he's "not worried" about a recent poll that has him trailing Stephen Harper and Thomas Mulcair as Canadians' most trusted economic manager.

An exclusive Nanos Research poll for CTV News asked respondents: "Whom do you trust to manage the economy?" Trudeau was the third-most common choice as Canadians' preferred economic manager, with 18 per cent support. The Conservatives' Stephen Harper and NDP Leader Thomas Mulcair were tied for first in the poll at 31 per cent support for each.

In an exclusive interview with CTV Morning Live in Ottawa, Trudeau downplayed the poll results. He also emphasized that he's "excited" by the conversations he's had with Canadians on the pre-election campaign trail.

"They want real change that's going to change the approach of government," Trudeau told CTV Morning Live in Ottawa on Thursday.

According to the Nanos poll, Trudeau might be right about the appetite for change. The poll found 66 per cent of respondents agreed that it was "time for change" in the federal government.

Trudeau suggested his party's economic policies will set it apart from the Conservatives and NDP.

"Mr. Harper has a plan that's not working, and Mr. Mulcair doesn't seem to have a plan for the economy," he said.

He also accused Harper of waiting until an election year to invest in transit projects in major cities such as Ottawa and Toronto.

"It's frustrating," Trudeau said. He added that his Liberals will push for more investment in transit and other infrastructure projects, "particularly around jobs and housing."

Election call on Sunday?

Prime Minister Stephen Harper is thought to be pondering an election call as early as Sunday. That would trigger a potentially lengthy election campaign ahead of an Oct. 19 vote, which many experts say will benefit the Conservatives the most.

The Conservatives are said to have a significant war chest of money saved up for the election campaign, and a long campaign would allow them to flex that financial muscle over their opponents.

CTV political analyst Scott Reid says Harper appears to be taking a strategic "election through exhaustion" approach, with a drawn-out campaign that will force the Liberals and NDP to be frugal in their spending.

"The Prime Minister wants to exhaust the budgets of his opponents," Reid told CTV's Canada AM on Thursday.

He added that it would be a good strategic move for Harper to call the election over the long weekend, so people "pay less attention and are less engaged."

Reid says Harper has a better chance of maintaining his status quo if people hungry for change are not engaged in the campaign.

Appetite for change

Pollster Nik Nanos of Nanos Research points out that the desire for change may not be enough to sweep Harper out of office. "If you get 35 per cent of the vote, you can still win the election," he told CTV News Channel on Thursday.

Nanos says election campaigns often start with voters eager to kick out the ruling party, but that desire for change can dissipate once voters go to the ballot box.

"They go through the whole election and then they realize they're not voting for perfection, they're voting for comparative choices," he said.

Nanos says Harper's Conservatives should be concerned by the desire for change, but they can still win the election if they are "comparatively better than the New Democrats and the Liberals."

"There's a significant proportion of Canadians that are ready to see something different," Nanos told CTV News Channel on Thursday. "The question is, is it enough to change the government?"

The cost of an extended election campaign

If Harper does trigger an election on Sunday, the resulting 11-week campaign would be the longest federal campaign since 1926. It would also be significantly longer than the typical five-week campaigns we've seen in recent decades.

The Conservatives have the money to bleed their opponents over a long election campaign, but such a campaign will also carry a steep price tag for taxpayers. Party candidates can seek a 60 per cent rebate on their campaign expenses through Elections Canada, meaning the longer the election campaign runs, the more money they'll be able to get back from the federal coffers.

The Harper government has already passed legislation that will allow candidate and party spending to balloon by as much as $675,000 for every day after the first 37 days of the election campaign.

A longer election will also mean higher administrative costs for Elections Canada.