When the US offered a larger sum of money for more mexican territory, how much more territory was the US asking for? I read somewhere that it would have included baja california and most of northwest mexico but I'm wondering what the exact extent of 'northwest mexico' means.
Meaning, I want to know what would the boundary between the US and Mexico would be today if the larger deal was taken?
The original Gadsden purchase included most of the current Mexican states of Baja California, Baja California Sur, Coahuila, Chihuahua, Sonora, Nuevo León, and Tamaulipas.
The USA didn't pay attention to what the actual Mexican state borders were. They wouldn't be taking just whole Mexican states, just whichever parts they wanted. Borders tended to be rivers (Rio Grande), straight lines, or sometimes, along continental divides. As for what was being talked about, more or less the maximum extent that was seriously discussed was Mexico down to the 25th parallel, plus all of Baja, and maybe the Gulf Coast as far as Tampico.