Rand's notes indicate that she modeled him on President Harry S. Truman, and that she deliberately decided not to call him "President of the United States" as this title has "honorable connotations" which the character does not deserve.
ɹˈændz nˈoʊts ˈɪndᵻkˌeɪt ðæt ʃiː mˈɑːdəld hˌɪm ˌɔn pɹˈɛzɪdənt hˈæɹi ˈɛs. tɹˈuːmən, ænd ðæt ʃiː dᵻlˈɪbɚɹətli dᵻsˈaɪdᵻd nˌɑːt tə kˈɔːl hˌɪm "pɹˈɛzɪdənt ʌvðə juːnˈaɪɾᵻd stˈeɪts" æz ðɪs tˈaɪɾəl hˈæz "ˈɑːnɚɹəbəl kɑːnətˈeɪʃənz" wˌɪtʃ ðə kˈæɹɪktɚ dʌznˌɑːt dɪzˈɜːv.