FEC - Presidential Campaign Finance: Provides current presidential filings of all candidates; contribution search by donor, employer, city or zip code; interactive state map

Politics1 - Presidency 2016: List of potential presidential candidates, grouped by political party, with links to their websites and social media networks

Wikipedia - Category: Gubernatorial Elections in the United States: Directory of encyclopedia articles about the campaigns, candidates and elections for state governors

Wikipedia - Category: United States House of Representatives Elections: Directory of encyclopedia articles about the campaigns, candidates and elections for U.S. Representatives

Wikipedia - Category: United States Senate Elections: Directory of crowd-sourced encyclopedia articles about the campaigns, candidates and elections for the U.S. Senate