I think the folks in Latin America refer to the people of Canada as "canadians".
As I mentioned in Post #55, the colonists who occupied the area that eventually became the United States (and Canada, for that matter) were called Americans by the world powers of the day long before there was a United States or a Canada.
The formal title of the Declaration is:
The Declaration of Independence of the Thirteen Colonies
In CONGRESS, July 4, 1776
The date was followed by a subtitle ending in a comma, which led to the first paragraph. The subtitle is:
The unanimous Declaration of the thirteen united States of America,
The concluding paragraph of the declaration begins as follows:
We, therefore, the Representatives of the united States of America, in General Congress, Assembled,
Notice that the founders used the grammatical formulation of a lower case 'u' in united, and capitalized 'States of America.' This emphasized that each of the states considered itself a sovereign nation, and that each of the sovereign states were united in declaring their independence.
The Declaration was, obviously, written in 1776. By 1787, after independence was won, and when the Constitution was written, the grammatical form changed to capitalize the 'u' in United, making that word part of the new nation's formal name. You can see it in the Constitution's preamble:
We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.
You can also see it in the Constitution's last original article:
Article. VII.
The Ratification of the Conventions of nine States, shall be sufficient for the Establishment of this Constitution between the States so ratifying the Same.
done in Convention by the Unanimous Consent of the States present the Seventeenth Day of September in the Year of our Lord one thousand seven hundred and Eighty seven and of the Independence of the United States of America the Twelfth In witness whereof We have hereunto subscribed our Names,
Thus, we are Americans, not in the broader context of the names of the two continents of this hemisphere, but in the strict context of the 228-year-old formal name of our nation.