GOP’s Senate hopes energized by Koch network ad blitz – Center for Public Integrity
https://publicintegrity.org/federal-politics/gops-senate-hopes-energized-by-koch-network-ad-blitz/
Koch Brothers’ Budget of $889 Million for 2016 Is on Par With Both Parties’ Spending - The New York Times
https://www.nytimes.com/2015/01/27/us/politics/kochs-plan-to-spend-900-million-on-2016-campaign.html