One of those gains may be a riding in Montreal where he received an award from the city's influential Jewish Community Council.
The riding of Mount Royal is up for grabs this fall with Liberal MP Irwin Cotler stepping down.
About 30 per cent of the riding identified as Jewish in the last census — making the electoral district one of only a handful in the country where that community can swing an election if it votes en masse.
The Liberals have held the seat since 1940, but the Jewish Community Council, a religious organization, has given its stamp of approval to Harper. It gave the prime minister its King David Award Thursday evening.
"The King David Award is presented to an individual who is a light unto the world," reads a description of the honour on the event's Facebook page. "One whose courage, strength, intelligence and faithfulness are examples and inspirations for us all.
"This year’s honouree has gone over and above the call of duty in every one of those attributes."
Harper's vocal support for Israel has drawn consistent praise from many segments of the Jewish community, who traditionally voted for the Liberals.
Nowhere is that shift clearer than in Montreal.
Just before Harper received the council's King David award, speaker after speaker praised the prime minister as a great friend of Israel.
Keynote speaker Ronald S. Lauder, the president of the World Jewish Congress, said Harper has never tolerated anti-semitism and has fought against it all his life.
"Allow me to take this opportunity to say thank you — thank you for standing with Israel," he said. "Thank you for standing with the Jewish people and thank you for staying on the right side of Israel and history."
"Let me say this unequivocally: Israel has no better friend than Prime Minister Stephen Harper," Lauder said to loud applause from the crowd of more than 600.
During his remarks, Harper said he was very touched and honoured to receive the King David award — "One for which, in all honesty, I'm not sure I or anyone else, could really ever truly measure up to."
He also used strong language to say that Canada remains steadfast in its support of Israel.
"Israel is the frontline of free and democratic nations and any who turn their back on Israel, or turn a blind eye to the nature of Israel's enemies do so, in the long run, at their own peril," Harper said.
"So Canada will continue to stand by Israel through fire and water."
The Conservatives last won Mount Royal in 1935 and it was Pierre Trudeau's seat for almost 20 years. In 2011, Cotler won with 41 per cent of the vote; three years earlier, he took 55 per cent.
The candidate the Conservatives ran in Mount Royal in 2011 was Saulie Zajdel, who upon losing was hired by then-heritage Minister James Moore to do "ethnic outreach" on behalf of the government.
Cotler often referred to him as a "shadow MP," accusing him of doing MP-like duties in the riding while being paid by taxpayers.
Zajdel quit in 2012. The next year, he was arrested in a corruption probe linked to former Montreal mayor Michael Applebaum. The case is set to be heard next month.
In the 2015 campaign, the Conservatives are fielding Robert Libman, a prominent former provincial politician. He'll face off against the Liberals' Anthony Housefather, mayor of Cote Saint-Luc.
While the Conservatives have their eye on this seat, they see more room for growth in other regions of Quebec, specifically around the capital and further north.
Currently, there are only five Conservative MPs from Quebec and one isn't running again. International Development Minister Christian Paradis announced earlier this year he won't stand for re-election.
But rather than take that as a hit, Conservatives say they actually see it as an opportunity to bring another new voice to their slate of candidates in order to breathe new life into their political fortunes.
That roster to date now includes popular municipal and provincial politicians and the former head of Quebec City's iconic winter carnival, all joining the team as polls suggest support for the Conservatives in Quebec is on the upswing.
The party attributes the gains to its policies on the economy and national security.
"If you look at the position of our party compared to the positions of the other parties, I think it's clear we are far closer to Quebecers on these issues, so I am optimistic, " Harper said Thursday at the Montreal airport, where he announced funding for RCMP and border agents.
"Quebecers also now have four years of NDP MPs to ask themselves what that got them, and I think the answer to that is pretty obvious."
With files from Peter Rakobowchuk
Note to readers: This is a corrected story. An earlier version incorrectly referred to Anthony Housefather as a former mayor. He is in fact mayor of Cote Saint-Luc.
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