What is the source exactly ? Because to my knowledge, the internet contains text in other languages than English. Did you filter the data ? Did you translate the foreign words ?

Did you use only American websites for your count ? Because "Republicans", "guns" and "abortion" are quite specific to the US. The given source must be more precise than "the internet".

Is "domestic" relative to the country where the movie was produced? If so, there should be a label with the country next to the movies' names.