Koch Network Raised Over $400 Million in 2012
"The Koch network alone raised nearly as much as the Romney campaign, and tens of millions more than GOP presidential candidate John McCain raised for his entire 2008 campaign. By design, following the Koch money trail is extremely difficult. Despite the groups spending hundreds of millions influencing elections, most of their spending and the sources of their funds are not reported to the Federal Elections Commission, earning them the moniker "dark money" groups.
Money is passed from one organization to the next, both to give donors an extra layer of anonymity and to help groups retain their tax exempt status. Nonprofits are not supposed to have electoral intervention as a primary activity, and the Koch groups apparently claim that transferring funds to other politically-active nonprofits should be counted as advancing "social welfare" rather than electoral activity."