For example, an audio-visual recording of an on-the-record interview between a journalist and a politician WOULD be considered a primary source produced through the interview process. A political speech, transcribed and archived by a librarian, WOULD also be a primary source.
On the other hand, an opinion on statements made by a politician, even if written by a knowledgeable researcher, would NOT be a primary source of the politician (unless it is the opinion of that politician).
The key difference here is that a primary source is fundamentally the representation of a moment or series of moments, depicted by a person who directly witnessed or experienced those moments -- NOT a person analyzing those same moments through reports made by others.
Primary sources available through library systems are assigned one or more standardized subject headings. Attaching these designated terms to a source's library record ensures that all primary sources relating to the same overall topic are able to be located in a single search, even when more specific keywords in the items' library records are different. For example: primary sources relating to Edward Snowden AND primary sources relating to Chelsea Manning would show up in a search using the subject heading "whistleblowing". To find sources relating to a particular subject: (1) explore the library record that describes a primary source you find interesting, (2) locate the subjects attached to that library record, (3) click the linked subject headings or copy and paste one into your search string, (4) limit your search to primary sources.
To help you identify and then use targeted terminology in your search strategy, start by first gaining an understanding of the person's ideologies or platforms through the lens of a nonpartisan reference or collaborative information source. Ballotopedia is my preferred resource, and Wikipedia is often an acceptable starting point (check Wikipedia's references and links to find additional resources)!
You can also use this tabbed box to browse keywords relating to primary political sources.
More established politicians may also have worked with publishing and production companies to create:
You can also find digitized official documents and data collections like: