South Carolina Sen. Lindsey Graham on Monday ended his bid for the Republican presidential nomination, exiting the race after using his campaign to draw attention to national security issues.

He made the announcement in a video posted on his campaign website.

“Today I’m suspending my campaign for president,” he said.

The three-term senator has struggled to gain traction in the race, and has been relegated during recent debates to the evening program with lower-polling candidates -- and even failed to qualify for one of them.

But he has stood out during those debates with his passionate appeals to confront Islamic terrorism.

In his video message, Graham stressed that “the centerpiece of my campaign has been securing our nation” and maintained he has brought needed attention to that issue.

“I got into this race to put forward a plan to win a war we cannot afford to lose and to turn back the tide of isolationism that was rising in our party. I believe we have made enormous progress in this effort,” Graham said.

Graham said that when he entered the race, no other candidates would join him in calling for more U.S. troops to confront the Islamic State.

“Today most of my fellow candidates have come to recognize this is what’s needed to secure our homeland,” he said.

He also sent an email to supporters announcing his decision.

Fellow candidates praised Graham as he bowed out, with Jeb Bush tweeting:

Only a handful of candidates have exited the crowded Republican race since the start of the campaign. With his decision, Graham joins former Texas Gov. Rick Perry, Wisconsin Gov. Scott Walker and Louisiana Gov. Bobby Jindal.