In an open letter published in La Presse on Tuesday, Conservative Leader Andrew Scheer invited Quebecers to give his party another look, citing Prime Minister Justin Trudeau's "incompetence" and the "existential crises" crippling the Bloc Québécois.

The Conservatives spy an opportunity in Quebec. And given the party's growing support in the province, they might be right.

Quebec was the only province in which the Conservatives made gains in the 2015 federal election. Their increase in the popular vote there was modest — just 0.2 percentage points, up to 16.7 per cent — but their seat haul jumped by seven to 12, the most seats the party has won in Quebec since the days of Brian Mulroney.

Further gains looked doubtful after the Conservatives lost a seat in a byelection held in Lac-Saint-Jean in October. But recent polls suggest that the party has seen a boost in support in Quebec over the last few weeks.

The CBC's Poll Tracker, an aggregation of publicly available polling data, puts the Conservatives at 21 per cent in Quebec, an increase of five points since the beginning of the year. That still puts them well behind the Liberals — who lead with 40.7 per cent — but it does open up some possibilities for them in parts of the province.

The Poll Tracker model suggests that the Conservatives could see their seat total increase to between 13 and 16 seats at these levels of support, with potential gains being made in Quebec City, the Saguenay–Lac-Saint-Jean region and the swath of territory lying between Montreal and the provincial capital.

Liberals, Bloc fall as Tories, NDP rise

Despite the Liberals' lead in Quebec, the party has seen its support erode recently. The Liberals are down almost seven points since the beginning of January.

The New Democrats, at 18 per cent, have picked up a couple of points.

The turmoil within the Bloc Québécois — seven of its 10 MPs left caucus last month in protest over Martine Ouellet's leadership — has cost that party some of its support. The Bloc has dropped three points in only the past few weeks and is now at 14.2 per cent.

The party was polling as high as 22 per cent in October. Its recent tumble has pushed it from second to fourth place in Quebec.

Polls suggest the Bloc Québécois has taken a hit under Martine Ouellet. (CBC)

Scheer's open letter made an appeal both to federalists disappointed with the Liberals and nationalists tired of the Bloc's internal spats. It's virtually the same pitch that Stephen Harper made to Quebecers in the 2006 federal election. Back then, it helped his party jump to 24 per cent support and 10 seats in Quebec after being shut out of the province in 2004.

Scheer made no such pitch to NDP voters. The leap to the Conservatives might be a leap too far for the NDP's remaining supporters in Quebec to make — including those nationalist voters who might be turned off by NDP Leader Jagmeet Singh's wearing of religious symbols.

But at this stage, the Conservatives are only in a position to pick up a handful of extra seats. The party would need to significantly reduce the Liberals' support in Quebec before seeing more than three or four more seats fall into their hands.

And Quebec remains the linchpin of the Liberals' re-election strategy in 2019. Their recent polling drop in the province is not large enough to cost them much in the seat count. The party could win up to 65 seats in Quebec at current levels of support, a gain of 25 seats over its 2015 performance — and perhaps enough to make up for losses the Liberals could suffer in other parts of the country.

Jumping on the CAQ bandwagon?

The opportunity presented by the Liberals' slide in popular support and the Bloc's self-destruction coincides with changing fortunes at the provincial level that could bode well for the Conservatives.

The Coalition Avenir Québec, a centre-right nationalist party led by François Legault, is currently leading in the polls in Quebec. The CAQ shares some of the same voters with the Conservatives — the party is most popular in the Quebec City region, where the Conservatives hold most of the federal seats.

That raises the tantalizing prospect of gains around Montreal. According to a recent poll by Léger, the CAQ is in first place in the Greater Montreal region, with a significant lead in the surrounding suburbs.

The Conservatives haven't won seats in the Montreal region since the 1980s, but the Conservatives did finish second in most of the area's ridings in 2006. At this stage, however, Scheer's Conservatives still have much work to do before a Montreal-area seat becomes winnable.

Scheer's profile in Quebec is still low

Scheer also has a lot of work to do before Quebecers get to know him better. Léger found that 48 per cent of Quebecers don't have an opinion of the Conservative leader, 10 months after he won the leadership.

On measures of Quebecers' preferences for prime minister, Trudeau outscores Scheer by a wide margin. But Scheer might look like a good option for disillusioned nationalist voters: Léger found that 51 per cent of Quebecers are dissatisfied with Ouellet's performance as Bloc leader, compared to just 15 per cent who gave her a thumbs up.

The first test of Scheer's appeal in Quebec will come soon. A byelection to replace former Liberal MP Denis Lemieux in the Saguenay–Lac-Saint-Jean region seat of Chicoutimi–Le Fjord must be called by June. The Conservatives are running a high-profile candidate in Richard Martel, former head coach of the Chicoutimi Saguenéens junior hockey team.

It is a seat that should already be high on the Conservatives' list of potential gains in Quebec in 2019. So that's where Scheer's attempt at a grande séduction begins.

On the latest episode of Pollcast, host Éric Grenier discusses the Conservatives' chances in Quebec with the CBC's Nick Gamache and what went down at the Ontario PC leadership event with the Globe and Mail's Justin Giovannetti.

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