Volunteers at the Lincoln Memorial help roll up a giant banner printed with the Preamble to the Constitution during an October 2010 demonstration against the Supreme Court's Citizens United ruling. Chip Somodevilla/Getty Images hide caption

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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. Alex Wong/Getty Images hide caption

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Costumed demonstrators on Oct. 3 in Denver, before the first presidential debate. Doug Pensinger/Getty Images hide caption

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Sen. Jon Tester, D-Mont., faces a potentially tough re-election bid. Win McNamee/Getty Images hide caption

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