Great New York Times editorial about campaign finance.

For all the headlines about the Tea Party and blind voter anger, the most disturbing story of this year’s election is embodied in an odd combination of numbers and letters: 501(c)(4). That is the legal designation for the advocacy committees that are sucking in many millions of anonymous corporate dollars, making this the most secretive election cycle since the Watergate years.
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Corporations got the power to pour anonymous money into elections from Supreme Court and Federal Election Commission decisions in the last two years, culminating in the Citizens United opinion earlier this year. The effect is drastic: In 2004 and 2006, virtually all independent groups receiving electioneering donations revealed their donors. In 2008, less than half of the groups reported their donors, according to a study issued last week by the watchdog group Public Citizen. So far this year, only 32 percent of the groups have done so.

Most of the cash has gone to Republican operatives like Karl Rove who have set up tax-exempt 501(c)(4) organizations. In theory, these groups, with disingenuously innocuous names like American Crossroads and the American Action Network, are meant to promote social welfare. The value to the political operatives is that they are a funnel for anonymous campaign donations.

Mr. Rove’s group, American Crossroads, hopes to spend $50 million, and is already advertising against Democratic candidates in California, Pennsylvania, Nevada and other states. The American Action Network, led by Norm Coleman, the former Republican senator from Minnesota, is spending $25 million, and has been blasting the Democratic senators Patty Murray in Washington and Russell Feingold in Wisconsin.