How do you stop states and cities from forcing more disclosure of so-called dark money in politics? Get the debate to focus on an “average Joe,” not a wealthy person. Find examples of “inconsequential donation amounts.” Point out that naming donors would be a threat to “innocents,” including their children, families and co-workers.

And never call it dark money. “Private giving” sounds better.

These and other suggestions appear in internal documents from conservative groups that are coaching activists to fight state legislation that would impose more transparency on the secretive nonprofit groups reshaping U.S. campaign finance.

The documents obtained by ProPublica were prepared by the State Policy Network, which helps conservative think tanks in 50 states supply legislators with research friendly to their causes, and the Conservative Action Project (CAP), a Washington policy group founded by Edwin Meese, a Reagan-era attorney general.

Dark money is the term for funds that flow into politics from nonprofit groups, which can accept donations of any size but, unlike political action committees, are not required by federal law to reveal the identities of their donors. The anonymity has been upheld by courts that cite as precedent a 1958 Supreme Court ruling that the state of Alabama could not demand that the NAACP turn over a list of its members.

Since 2008, dark money groups have spent more than $690 million in federal races, according to the Center for Responsive Politics. A single group aligned with Republican presidential hopeful Marco Rubio helped buoy his standing in Iowa before Monday’s caucuses with $1.3 million in ads.

The same story is playing out on the state level. During the 2014 election cycle, 40 nonprofits spent $25 million on TV ads about state races, according to an analysis by the Center for Public Integrity. That represented 3 percent of total ad buys, almost double the proportion that dark money paid for in 2010.

This year, 38 states are considering bills relating to disclosure, according to a database compiled by the National Conference of State Legislatures. Some have already adopted rules. In 2014, California began requiring nonprofits that engage in campaign activity to live by many of the same disclosure regulations as traditional political committees. Montana decided last year that politically active nonprofits would have to disclose donors, and report any electioneering communications within 60 days of votes being cast.

A memo distributed by CAP in January to conservative activists highlighted new disclosure rules being considered in Minnesota, Missouri, New Mexico, Pennsylvania, Tennessee, and Washington, as well as ethics bills in South Carolina and Texas that contain disclosure provisions.

Groups that are throwing their resources behind stricter campaign finance regulation include Common Cause, which has offices in 36 states, and the Democracy Alliance, an invitation-only organization composed of wealthy liberal donors. According to CAP, though, the initiatives to require disclosure not only pose a threat to free speech but also to the very existence of the nonprofits.

“This well-coordinated, well-funded effort to require conservative nonprofits like yours to divulge the names and addresses of your donors is all part of a plan to choke off our air supply of funding,” the group said in the memo.

The memo was signed by many leading voices on the political right, including anti-tax advocate Grover Norquist; top officials at Americans for Prosperity, an advocacy group backed by the Koch brothers political network; the Family Research Council; the Council for National Policy; and Heritage Action for America. It describes conservatives as “a persecuted class” and compares labeling private donations “dark money” to calling private ballots “dark voting.”

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