Funny things happen in by-elections. Voters who would normally go to the polls in a general election to choose a government can't be bothered turning out for a by-election.
Those who are dissatisfied, either with the government or the party they usually support, might show up to cast a protest vote, while those who are content stay home. Those who are unhappy with a party at another level of government might take it out on that party's ally.
And supporters of the Parti Québécois can be especially difficult to motivate to participate in an election that won't bring them closer to sovereignty.

That's why, even though no major party leader has ever lost a provincial by-election in Quebec, Pauline Marois's victory in Charlevoix riding Sept. 24 isn't quite a sure thing.
Indeed, the new PQ leader's choice of Charlevoix in which to make her return to the National Assembly, from which she resigned after losing the leadership to André Boisclair two years ago, is puzzling.
Marois was offered the choice of several seats held by PQ MNAs apparently eager to get out of active politics after the party sank to third place in the March 26 election.
Charlevoix isn't the safest PQ seat. It did vote PQ in the last four general elections, but by fewer than 2,000 votes in each of the last two, while the PQ was losing province-wide.
The riding, on the north shore of the St. Lawrence between Quebec City and the Saguenay River, is officially in the provincial capital region.
So Marois's presence there might flatter voters in a region that has become a political battleground contested by all three parties in the Assembly.
But even though Marois was born, raised and educated in Quebec City and has a summer cottage in Charlevoix, she remains an outsider in a predominantly rural area with a strong sense of identity.
Her main opponent, Conrad Harvey of Mario Dumont's Action démocratique du Québec, has zeroed in on her vulnerability. Harvey, who was born and lives in the riding and ran there for the ADQ in the general election, has said of Marois that "the blood of Charlevoix doesn't flow through her veins."
Harvey nearly doubled the ADQ's vote in the riding in the general election, moving the party ahead of the Liberals into second place. And with a minority government in office, he said he hasn't stopped campaigning since the general election.
The wild card in this by-election is the orphaned Liberal vote of more than 6,000 in the last general election. The Liberals aren't running a candidate in the by-election, ostensibly to facilitate Marois's joining the two party leaders in debate in the Assembly.
But the Liberals might have another reason for wanting Marois to win. The main threat to both the Liberals and the PQ now comes not from each other, but from the ADQ.
Poll results published yesterday suggest PQ gains in popularity since Marois became leader in late June came at the expense of the ADQ, not the Liberals.
A defeat for Marois, however, would bring the usual honeymoon between a new leader and public opinion to an early end, and might plunge the PQ into crisis and strengthen the ADQ.
By saying he wants Marois in the Assembly, Premier Jean Charest has sent a not-too-subtle message to Charlevoix Liberals. Still, it's an unnatural act for Liberals to cast even a strategic vote for the PQ, their longtime archenemy.
They could abstain, or vote for the candidate of the Green Party, which has become the choice of voters who don't want to make a choice. That's what many did in a 2006 by-election in which their party did not run a candidate against Boisclair, whom Charest was eager to face in the Assembly.
But that was in Pointe-aux-Trembles, a safe seat for the PQ, and there was no ADQ candidate with a chance of upsetting the PQ leader. In Charlevoix, the candidate for the "autonomist" ADQ is appealing to Liberals by presenting himself as a federalist. And if enough Liberals succumb to the temptation to try to defeat Marois and thereby strengthen the ADQ, then their party's decision not to run a candidate might end up backfiring against it.

dmacpher@thegazette.canwest.com