According to the Center for Responsive Politics, the number of dark money ads decreased in this election cycle once reporting requirements kicked in and donors had to disclose their contributions. In other words, donors prefer to spend money to influence politics when they can do it in secret.
“We’re seeing dark money groups that have spent millions of dollars in Senate races fade away, rather than report their spending to the FEC,” said Sheila Krumholz, executive director of the Center for Responsive Politics.
The so-called “spending plunge” took place after the Federal Election Commission’s reporting window opened on September 9th. Before that date, 42% of ads by outside spending groups were paid for by dark money groups; afterward, that figure dropped to just 11%.
Read the full report here: https://www.opensecrets.org/news/2016/10/dark-money-ads-plunged-when-reporting-requirement-kicked-in/.