The document summarizes key aspects of federal campaign finance law before and after the Citizens United Supreme Court decision. It discusses how Citizens United struck down limits on independent corporate spending in elections and led to a rise in spending by super PACs and 501c4 nonprofit groups. While Citizens United allowed for increased political spending, the document notes the dicta in the decision around freeing nonprofits from political activity limits could be used to mount further legal challenges but may not be successful in the near term.