It was amended in 1974 to place legal limits on the campaign contributions. (politics.stackexchange.com)
More than $ 1.6 million was spent on campaign contributions in 2011 from just four of the top five oil companies. (grist.org)
The federal «pay - to - play» rule does contain one exception: If bond contracts are awarded by competitive bidding, then the prohibition on campaign contributions does not apply. (ibtimes.com)