US Senator Lindsey Graham, a respected conservative voice on defence and foreign policy issues, dropped out of the 2016 Republican presidential race on Monday after months of barely registering in opinion polls. Graham struggled to gain traction in a crowded Republican field dominated by front-runner Donald Trump, and he faced the potentially embarrassing prospect of being trounced in the February 20 primary in his home state of South Carolina.
Graham, an early and staunch advocate of using US ground troops against Islamic State, said his long-shot campaign had made headway in influencing the party's debate on the conflict. "I got into this race to put forward a plan to win a war that we cannot afford to lose, and to turn back the tide of isolationism that was rising in our party. I believe we've made enormous progress in this effort," he said in a video posted on YouTube.