Why is the petroleum reserve in Iraq a factor in the election?

So according to ‘The President’ at the beginning of the 2003 invasion of Iraq oil was not a factor. Now however , prior to the election we are supposed to be concernecd that the ‘civil war’ in Iraq could threaten our oil supply in the US. How is that possible when two-thirds of our nations oil imports come from Canada?
Interesting, isn’t it?