So here's the baseline spiel:
North and S. America look nothing like they do today. We have instead
1 nation covering pretty much all of current Canada plus Vermont and Maine-we'll keep this as Canada. (Anglophone majority)
1 nation covering rest of New England (naturally enough this is New England)(Anglophone)
1 nation across the South (ok the CSA to keep various people happy)(Anglophone with African American majority population)
1 rump USA
1 nation of California, New Mexico and a few other territories-call this California, Pacific States of America-whatever you fancy.
1 Texas-pretty much as now-perhaps enlarge with some additional gained territories (minority and ruling group Anglophone, rest Spanish/native)
1 Carribean and Floridean nation of Florida, you can also include as many Carribean elements in the near vicinity (not as far as T&T though)(Anglophone with minor Spanish)
1 Hispaniola plus Carib states (one collective nation -West Indies and Hispaniolan Federation)(as Florida)
1 Mexican state (perhaps lost some of its territory to Greater Texas and/or California)(Mixed population as now, Spanish speaking)
Brazil and Northern Latin America are unchanged, Patagonia is settled far earlier by British settlers (pop mix of indiginous and Anglo descended)
So work out how its got there and what are they like, possible ramifications etc....