US President Donald Trump has thrown his support behind Senator Darline Graham ahead of Tuesday’s Republican Senate runoff in South Carolina, urging his supporters to turn out and vote for his preferred candidate. Trump told a rally in Myrtle Beach that voters should back Graham as she seeks a full Senate term. Graham is serving the remainder of the term following the death of her brother, Senator Lindsey Graham, in July. Trump linked her campaign to his America First agenda and preserving tax cuts, while his rally speech also touched on illegal immigration, border security, Iran and the proposed White House ballroom.