> Canadian federal governments are generally comprised of whichever party received the largest share of votes nationally. This is not always the case in the US.

I'm going to disagree with you on this. In Canada, the general votes usually result in 1/3-1/3-1/3 split between the Conservatives, Liberals, and NDP. It's our first past the post system for MPs that results in the uneven split at the final tally. The only reason that the system hasn't succumbed to gerrymandering as badly as elsewhere is that district changes must be prompted by a change in the number of provincial seats from the census. The changes themselves are proposed by an unelected third-party with members chosen by the judiciary of the province and the speaker of the house (who is chosen by the MPs through a secret ballot vote). Otherwise, it would be all too easy to gerrymander an election in Canada and end up in the same situation as the US.