View the original community article here
Last tested: Mar 7, 2019
According to our documentation, "us_states - Accepts full state names and two-letter state abbreviations."
In testing, the state name must be in Capitalized format like "Florida". All caps like "FLORIDA" or all lower case like "florida" will not be mapped.
A user who had the names in all caps came up with this
State values with whitespace surrounding also won't be mapped - you can use a TRIM() function around the state column to ensure this is not an issue.