The ground is shifting in Quebec and tomorrow may give us a good sense of just where things are headed.

The races in Saint-Hyacinthe, Roberval and Outremont all look tight and the outcome is anybody's guess.

There is something at stake for all federal leaders in these by-elections though.

It's the reason you see Jack Layton's face plastered all over Outremont these days. He's hoping to pick up a seat in Quebec courtesy of his candidate, Thomas Muclair. It's something the NDP hasn't managed to do since 1990

Gilles Duceppe has been out in force too. He wants to show Quebecers his party is still relevant and to hold on to what are traditionally bloquiste strongholds in Saint-Hyacinthe and Roberval.

Stephen Harper hasn't been as present on the ground, but his ministers have been. He's hoping to pick up a seat to prove he has managed to connect with Quebecers.

And then there's Stephane Dion. Liberals won't openly say this is a critical test for his leadership, but plenty of other pollsters and pundits will. Outremont has been a Liberal stronghold for decades. A loss might cause Dion some problems he doesn't need.

On the ground though it's almost impossible to guage. By-elections traditionally have low voter turnouts. They are strange beasts: hard to understand and even harder to predict.

Count on one thing: there will be surprises - for everyone.