Canadian economic growth is about two percentage points higher under Liberal governments. At least, that's what my colleagues Stephen Ferris and Marcel Voia found in their recent article in the Canadian Journal of Economics (earlier ungated version here).
This is a large impact. For example, if the economy was growing at 1 percent under a Conservative government, switching to a Liberal government would increase the predicted GDP growth rate to around 3 percent.
The question is: why?