Although some argue that the United States is on its way out as a super-power, the reality is that many other countries will be directly affected by the outcome of the presidential elections.
Mr Romney loves Canadian oil and says the US should buy more of it.
"You know, the president doesn't face a lot of no-brainer decisions. But one of them was the decision of whether or not to have Canada's oil come here or go to Canada, and he failed. The answer is I'll build that Keystone pipeline if I have to build it myself, bring that oil here." - 18 July
Obama has called Conservative Prime Minister Stephen Harper "a trusted partner", and noted Canada is the number one trading partner.
"Perhaps no two nations match up more closely together or are woven together more deeply economically, culturally than the United States and Canada." - 7 December 2011