1. Thanks to redistribution, the riding itself won't exist in 2015
Oh, it's not being wiped off the map entirely, of course — in fact, the southern chunk will remain basically intact, with the Annex and nearby neighbourhoods moving into the existing riding of St. Paul's, a change that is ultimately likely to make the renamed Spadina-Fort York an even safer seat for the New Democrats, barring a major ideological shift on the local level.
The by-election, however, will be waged according to the old boundaries — which, pre-Olivia Chow, tended to favour the Liberals, although to be fair, that was back in the days when Toronto itself was viewed as a fortress for the red team.
(The Conservatives, meanwhile, can take some comfort, at least, in the fact that expectations for their performance in Trinity-Spadina are, if possible, even lower than was the case in Toronto-Centre.)
In any case, presuming, at least for the moment, that a 2011-like Orange Wave-inspired landslide doesn't bury their next candidate in by-electoral rubble, it's possible, albeit unlikely, that the Liberals might have a shot at recapturing Trinity-Spadina.
Even if they did, however, it wouldn't necessarily make it any more likely that they'd hang onto it in 2015.
That said, if the Liberals don't at the very least narrow the eventual gap between their candidate and the NDP to single digits, it would be hard to see it as anything other than a blow to those counting on a continuing wave of Trudeaumania sweeping the Greater Toronto Area in 2015.
2. It's all — and always — in the timing
With Chow poised to join John Tory and — of course — Team Ford on the civic hustings, the battle for Toronto City Hall would seem to have begun, which would almost certainly relegate a late spring byelection to the political backburner, at least as far as media and public interest.
Federal hopefuls could also find themselves facing a relative shortage of willing foot-soldiers to fill their campaign offices and phone banks, particularly if Chow's civic bid pulls in volunteers — and, just importantly, strategy and intel — from across the centre-left political spectrum.
There's also a good chance the byelection itself could turn into into a sort of proxy advance ballot for the municipal race — although again, barring a true three-way race, it's hard to see how that would play off in what is likely to be a faceoff between the New Democrats and the Liberals.
Even if the PM were to put off calling the Trinity-Spadina byelection until the fall, depending on when House Speaker Andrew Scheer receives the official notice of vacancy, the deadline for dropping the writ would likely be no later than mid-September, which would mean the campaign would likely run straight through the mayoral election — or, alternately, vice versa.
Add to that the remote, but still mathematically possible chance that the provincial government could end up facing the electorate as well, and you've got the makings of virtually irreproducible electoral conditions.
3. As above, not necessarily so below
Byelections, it's worth noting, can be remarkably — and, from a journalistic perspective, at least, delightfully unpredictable, what with the off-season timing, the typically low turnout and the tendency of parties, pundits and, at least in theory, voters to occasionally see them as a referendum on the bigger federal political picture to a far greater extent than is the case in a general election.
Although history suggests that byelection winners usually get a return ticket to Ottawa from their next outing to the polls, that's not always how it happens — and, as noted in the preceding caveats, this particular byelection will likely take place against an over-arching political backdrop that is just as maddeningly mutable.
Add to that the laundry list of unknown factors — starting with the nomination process, which could easily spark internal skirmishing before the writ has even dropped — and it's easy to see why savvy political observers won't necessarily take what happens in Trinity-Spadina as a sign of election results to come.
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