I'll suggest:
1. New England Confederation declares independence during the War of 1812. Eventually growing close enough to Britain that it enters into a union with the Maritime provinces.
2. Quebec becomes a dominion within its own right within the British Empire.
3. Canada is granted dominion status during the 1850s. It incorporates the territory of British Oregon, originally jointly exploited by the Hudson Bay Company and New England interests, and Alaska, seized by the British during the Russian War.
4. The United States extends its Manifest Destiny southward into Mexico during the Mexican-American War. There is also the Spanish-American War of the late 1890s. Santo Domingo requests and is granted statehood, while Haiti is later occupied to keep European investors from collecting on its debt. The US annexes Hawaii in 1899.
5. Filibuster William Walker succeeds in seizing power in Nicaragua and eventually conquers all of Central America. The United States of Central America annex the failing Yucatan Republic in the 1860s.
I'm not quite sure if we are to include Siberia, Greenland, Colombia and Venezuela since they are colored.