Former Secretary of State Hillary Clinton campaigned for Maryland Democratic gubernatorial candidate Anthony Brown (right) in October. President Obama and Michelle Obama have also campaigned in the state. This level of Democratic star power so late in the race is unusual in a reliably blue state. Patrick Semansky/AP hide caption

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Florida Democratic gubernatorial candidate Charlie Crist, center, gets a kiss from a supporter after he stepped off his bus during a brief campaign stop at Delevoe Park in Fort Lauderdale, Fla., on Oct. 25. Wilfredo Lee/AP hide caption

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Laney Barroll Stark, of Savannah, Ga., took a picture with her cell phone as Rep. Jack Kingston, who ran for the Republican nomination for U.S. Senate in Georgia, addressed supporters at his primary runoff election night party in July. David Goldman/AP hide caption

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It's a long shot, but there's a scenario where control of the Senate might not be known until Jan. 6 — three days after the start of the next Congress. That's when Republican David Perdue and Democrat Michelle Nunn will face each other in a Georgia runoff if one of them fails to win 50 percent on Tuesday. David Tulis/AP hide caption

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Texas lieutenant governor hopefuls state Sen. Dan Patrick and state Sen. Leticia Van de Putte shake hands following a September debate. While most eyes are on the governor's race, this contest could have even more political consequence. Eric Gay/AP hide caption

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Former President Jimmy Carter and his grandson, Georgia state Sen. Jason Carter, watch a baseball game between the Atlanta Braves and Philadelphia Phillies in Atlanta on Aug. 14. John Bazemore/AP hide caption

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