Federal Conservatives had urged voters in Labrador to overlook spending violations in 2011 by incumbent Peter Penashue, who said he was guaranteed a cabinet post. He finished a distant second to Liberal challenger Yvonne Jones, the clear winner with just over 48 per cent of the vote.
Dunderdale said having no one in the majority Conservative government's inner circle will have an impact.
"It always makes it more difficult when you don't have somebody inside the tent," she said Tuesday outside the legislature. "But you know, we're charged with a responsibility to advocate on behalf of the people of the province.
"The federal government is responsible for all of the people in Canada, including the people of Newfoundland and Labrador. They have to listen to the legitimate aspirations of the people of this province, and assure us that we're being heard and responded to."
Dunderdale's Progressive Conservative government has tried to build bridges with Ottawa after years of fractious relations under her predecessor Danny Williams. Conciliation has worked on some issues but not others, such as search and rescue response, Dunderdale said.
Still, she stressed that she does not begrudge Labradorians the choice they made.
"I'm certainly not going to blame anybody for exercising their franchise and making decisions that they feel are in their best interests," she said.
Prime Minister Stephen Harper said Penashue knew he was in a tough fight in Labrador.
"Peter Penashue knew full well that this would be difficult," Harper said in French during a news conference in Summerside, P.E.I.
"At the same time, he was determined to do the right thing and therefore he made that decision. And we want to thank him for his service to Canadians."
Penashue's loss handed the Harper government its sole byelection defeat in a Tory-held seat since it took power in 2006. He resigned as intergovernmental affairs minister in March, saying he wanted to regain the trust of voters after he broke campaign spending rules during the 2011 federal election.
Even before the last polls closed Monday night, all three national parties were spinning the results to suit their causes. The Liberals said Penashue's defeat was a rejection of Conservative cynicism; the Tories said it was no surprise in a traditional Liberal riding, and the NDP said their base of support held strong at around 19 per cent of the popular vote.
Political scientist Kelly Blidook of Memorial University of Newfoundland said he wouldn't read too much into the outcome on a national scale. Nor does he think the results can accurately be cast as a first step toward better things for the federal Liberal party under its new leader Justin Trudeau.
"I think these are pretty predictable results given the reason for having the byelection in the first place," he said in an interview. "I wouldn't necessarily take this as some big sign that the Liberals did something amazing here, that Trudeau did something amazing."
Labrador has gone Liberal in all but two elections since the province joined Confederation in 1949.
Political scientist Henry Jacek, whose research includes how voters respond to ethical issues, believes Penashue overplayed his cabinet card.
"You see sometimes politicians who get into trouble of one kind or another make the case of, well, I'm part of the government. I'm going to be a cabinet minister. I'm going to have access to the government and I can do a lot more for you than an opposition (member).
"And people sometimes really get their back up about that," he said in an interview. "People feel they're just being manipulated and that it's really improper."
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