Alaska is considered among the Continental United States because it and the "Lower 48" are on the continent of North America.

The Contiguous United States excludes Alaska by definition, since Alaska does not share a border with any of the other United States.

Excluded from both categories, Hawaii is neither among the Continental nor the Contiguous states. Similarly, if Puerto Rico, Guam, or any of the other Territories of the United States were to become a state, they too would fall into the category of neither Continental nor Contiguous.

The only possibility being currently discussed would be if Washington, D.C. were to become a state. If this were the case, it would fit into both Continental and Contiguous categories.

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