"You're looking at him," McKay said when asked by reporters in Nova Scotia who would be replacing Penashue as Newfoundland and Labrador's voice at cabinet.
"And I've done it before. I've been the minister responsible for Newfoundland and Labrador in addition to Nova Scotia. I'm familiar with the province, the issues, and was there just last week."
After the 2008 election, in which Newfoundland and Labrador voters shut out Conservative candidates in the wake of an "Anything But Conservative" campaign that then premier Danny Williams unleashed against Stephen Harper, MacKay stepped in to represent the province in cabinet.
MacKay relinquished the role in 2011 when Penashue defeated Liberal incumbent Todd Russell to score the Conservatives' only win in the province.
Penashue, though, was forced to resign his seat and post as intergovernmental affairs minister in March amid an Elections Canada investigation which found his campaign accepted illegal contributions and spent too much.
"It's always preferable to have one of your own," said MacKay, who also said he is confident he can provide representation again.
MacKay said he has "a lot of affection and appreciation and understanding of the issues and of the people, most importantly, of Newfoundland and Labrador."
Meanwhile, MacKay said he did not see Monday night's result as a rebuke for the Harper government. He said he believed that Penashue had performed well, but was campaigning in a riding that only twice had broken with a tradition of electing Liberals.
"When one examines that history, one perhaps could see this was not a surprising result," said MacKay, who also believes it's hard for governing parties to hold seats.
"Governments very seldom win byelections. It is often the case that you don't come out on the winning side of a byelection in mid-term," he said.
Nonetheless, Penashue's loss marks the first time since 2006 that the Conservatives lost a byelection in a riding they had held.
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