Wisconsin Republican Gov. Scott Walker speaks in Milwaukee in May. Newly released documents show prosecutors are alleging Walker was at the center of a nationwide "criminal scheme" to illegally coordinate with outside conservative groups.
People wait in line for the beginning of the 2013-2014 Supreme Court term in Washington on Oct. 7. The court heard the first major case on campaign contribution limits since 2010's landmark Citizens United.
The Supreme Court denied the petition of businessmen who say the 2010 Citizens United ruling makes it legal for corporations to contribute directly to candidates. The court building is seen here during renovations in December.
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Karl Rove, former adviser to President George W. Bush, speaks last year in Corpus Christi, Texas. Rove is the chief fundraiser for the biggest outside spender this election season: the twin groups American Crossroads and Crossroads GPS.