The law expired after the ' ` ` Citizen 's United '' ruling by the Supreme Court in 2010 . Public matching funds apply only during the early primary contests , whereas major party presidential nominees qualify for a lump-sum grant that can be used for the general election in November . Super PACs can spend unlimited money but must disclose it . They use these funds to flood airways with political ads and ads supporting a particular candidate .
The law expired after the ' ` ` Citizen 's United '' ruling by the Supreme Court in 2010 . Super PACs can spend unlimited money but must disclose it . They use these funds to flood airways with political ads and ads supporting a particular candidate .