Demonstrators march in the snow outside the White House during a rally against the Supreme Court's decision five years ago in favor of Citizens United, which allows private citizens and corporations to make unlimited donations for political campaigns.
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Republican political operative Tyler Harber admitted in federal court to illegally coordinating between a campaign and superPAC. He was sentenced to two years in prison and two years' probation.
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Declared and potential candidates are already in New Hampshire. Former Florida Gov. Jeb Bush and others spoke at the First in the Nation Republican Leadership Summit this week in Nashua.
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Missouri Auditor Tom Schweich committed suicide following political attacks during his campaign for governor. His press secretary, Spence Jackson, committed suicide just one month later.
Chevron Corp. supported several candidates in Richmond, Calif., where the company has been hoping to modernize a large oil refinery, seen here in 2010. None of the Chevron-backed candidates were elected.
Scott Hildebrand, a Democrat, and Mike Jansen, a Republican, are competing to be the new sheriff in Campbell County, Ky., but they're also abiding by an agreement to keep their race clean.
Images courtesy of the candidates