Great idea... I think this will do it (starting from functions and data created in the notebook above):
text = <|# ->
partyPlatformImporter[IDset[#]["1960"]] & /@ {"Democratic",
"Republican"}|>;
counts = Counts /@ (TextWords[ToLowerCase[DeleteStopwords[#]]] & /@ text);
demOnly =
Complement[Keys[counts["Democratic"]], Keys[counts["Republican"]]];
repOnly =
Complement[Keys[counts["Republican"]], Keys[counts["Democratic"]]];
Row[WordCloud[KeyTake[counts[#party], #keys],
ColorFunction -> ColorData[#color], ImageSize -> 400] & /@ {<|
"party" -> "Democratic", "keys" -> demOnly,
"color" -> "AtlanticColors"|>, <|"party" -> "Republican",
"keys" -> repOnly, "color" -> "ValentineTones"|>}]