William C. McDonald began his career in law and education, studying at Cazenovia Seminary and teaching primary school in New York. He transitioned to the American West, apprenticing in Kansas and later moving to New Mexico, where he engaged in mining and ranching. McDonald's early political involvement included serving as Lincoln County Assessor and a member of the New Mexico Territorial House of Representatives. As the first Governor of New Mexico, he implemented significant labor and welfare laws, structured the state's government, and managed public safety issues. Post-governorship, he continued public service as New Mexico Fuel Administrator until his death.

William C. McDonald's political journey reveals a unique blend of local economic advocacy and frontier governance. His early career in mining and cattle ranching informs a pragmatic yet progressive approach to labor laws and public welfare. McDonald's tenure as governor saw him navigating complex regional security issues while simultaneously structuring New Mexico's nascent government. His legislative focus on working conditions and poverty relief hints at an ideological flexibility that balances traditional Democratic values with localized economic pragmatism.