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by NW Spotlight
A compilation of campaign contribution data shows that nationally, the top 15 donors are led by casinos (including Indian gaming [2]) and public employee unions (NEA, SEIU, AFSCME).
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The National Institute on Money in State Politics and the Center for Responsive Politics collaborated to compile a unique view of the top 10,000 donors to political campaigns [4] at both the state and national level. Their data is from state and federal campaigns, political parties, and ballot measure committees in 2007 and 2008.
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