US Senator Lindsey Graham said on Monday he is dropping out of the race for the 2016 Republican presidential nomination, leaving 13 candidates in the party's still-crowded field.
"Today, I'm suspending my campaign for president," the South Carolina senator said in a video posted on YouTube.
Graham, a hawk on defense and foreign policy, ranked in lowest tiers in opinion surveys of Republican voters in a race being dominated by a political outsider, real estate tycoon Donald Trump.
"I'm going to suspend my campaign. I'm not going to suspend my desire to help the country," Graham said. "I've hit a wall here."
Graham said he was proud of what he called his bold, practical solutions on debt and immigration.
"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.