Some nationalities are required visa to entry Brazil, USA is one of them.
Visit the consulate website to learn if your Country is required a visa to entry Brazil.
Citizens of United States do need a tourist visa to travel to Brazil and they can send the application by mail.
Please visit cgwashington.itamaraty.gov.br/en-us/ To learn which Consulate is near you.
There are Consulates in Washington (cgwashington.itamaraty.gov.br/en-us/), Miami (miami.itamaraty.gov.br/en-us/ )
Atlanta (atlanta.itamaraty.gov.br/en-us/), Chicago(chicago.itamaraty.gov.br/en-us/), Los Angeles (losangeles.itamaraty.gov.br/en-us/) New York(novayork.itamaraty.gov.br/en-us/ )
and San Francisco (saofrancisco.itamaraty.gov.br/en-us/)