Polls show the sister of the late Senator Lindsey Graham in a virtual tie with her Democratic opponent, Dr. Annie Andrews. An upset was unthinkable just a few months ago.

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Holding South Carolina is essential if Republicans have any hope of keeping their Senate majority.

South Carolina seems like a serious race; Minnesota may not be; and Florida still appears out of reach for Democrats.

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Senator Darline Graham, the South Carolina Republican, is struggling to replicate her late brother’s success. Republicans lead in the Florida Senate race and Democrats are up in Minnesota.

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Hope, dread and the final stretch to Election Day.

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President Donald Trump will visit South Carolina on Wednesday to boost Graham, whose stumbles in her first campaign since replacing her late brother have Democratic voters hopeful — but not necessarily optimistic — that their candidate can break Republicans' grip on the state.