This Pew Research Poll has all kinds of fascinating nuggets about the image of the United States globally. In general, the U.S. is seen pretty favorably in the Latin American countries surveyed (Argentina, Bolivia, Brazil, Chile, El Salvador, Mexico, and Venezuela).
The exception is Argentina, where the U.S. is viewed favorably by only 41%, though that is up from 17% in 2007. Argentina also highlights something that you don't hear much about: young Latin Americans view the U.S. in a more positive light than older.
The polls were conducted in March and April 2013, so of course do not reflect the current controversies, especially with regard to Bolivia. We might likely expect the views of the United States not to change all that much, but rather to see Obama's favorability drop. And, in fact, he is less popular than the "United States," which reflects the difference between the U.S. as a country and U.S. foreign policy. At the same time, though, there are interesting discrepancies, such as 51% of Venezuelans believing the United States takes their country's interests into consideration.
Further, Latin Americans tend to see China's economic influence as more positive than that of the United States, even while acknowledging that China protects civil liberties less.
Anyway, it's worth digging around in there.