The last act of the federal parliamentary season will take place on Monday in Ontario and Alberta - two provinces that were more than instrumental in paving the way to a Conservative majority three years ago.
But the similarities between the two sets of ridings at play in the June 30 byelections stop there.
In the last federal election the Conservatives won about three-quarters of the votes in MacLeod and Fort McMurray-Athabasca.
It would take a massive political shift or a massive failure on the part of the Conservative machine to get its vote out for a byelection sandwiched between a summer weekend and Canada Day for one of those seats to end up anywhere but in the government column on Monday.
On paper the stakes for the Conservatives in the two opposition-held Toronto ridings that will pick new MPs on Monday might seem modest. In fact, Stephen Harper's strategists will be paying close attention to the results in Scarborough-Agincourt and not only because they have been testing attack ads that caricature Justin Trudeau's marijuana policy.
Scarborough-Agincourt has the kind of profile that most closely matches that of the ethnically diverse suburban ridings that stand to determine the makeup of the next federal government.
The Liberals held the seat without breaking too much of a sweat over the course of three lost national campaigns. In 2011 - the Liberals' worst election year - the NDP, in spite of a spike in support at the end of the campaign, could still not do better than 18 per cent and the Tory candidate finished 11 points behind veteran MP Jim Karygiannis.
But incumbency was the saving plank of most of the Liberals who survived the 2011 debacle.
This time the dynamics are reversed. Monday's result in Scarborough-Agincourt will speak as much to the length of Trudeau's coattails in suburban Ontario as to the virtues of candidate Arnold Chan.
On that basis it is a must-win riding for the Liberals, a must-watch one for the ruling Conservatives and one where the NDP must do better than stand its ground if it is to be taken seriously by those voters whose primary goal next year will be to oust Harper from power.
And that brings one to Trinity-Spadina, the site of an NDP/Liberal battle so fierce that it has attracted intense national media coverage.
It is a battle Thomas Mulcair can ill afford to lose. For the Liberals, a victory in Olivia Chow's former seat would come as close as they could possibly hope to getting payback for their grievous Outremont defeat at Mulcair's hands in 2007.
That NDP victory poisoned the well of Stéphane Dion's nascent leadership. It convinced more than a few potential high-profile recruits to sit out the 2008 Liberal campaign, a trend that Michael Ignatieff was unable to reverse three years later.
A Liberal upset victory in Trinity-Spadina on Monday could have the same chilling effect on Mulcair's recruitment efforts.
It is not that diehard New Democrats would decline to run on his ticket next year. But if Mulcair is to successfully sell his party as the alternative to the Conservatives, he needs front-line candidates whose profile does not fit that of the usual NDP suspects and those will become harder to get if he fails to hang on to an iconic seat on Monday.
There could be at least one more hard-fought Ontario byelection battle before the 2015 election:
Harper must set a date to fill the late Jim Flaherty's Whitby-Oshawa seat by the end of October.
There had been suggestions that the prime minister had held off including the riding in Monday's mix in the hope that Christine Elliott, Flaherty's widow, would reconsider running federally. But the Ontario MPP has now thrown her hat in the provincial Tory leadership campaign, and her absence could make for a more level playing field in the federal byelection.
Chantal Hébert is a national affairs writer.