On the last day for candidates to remove their names from the South Carolina primary ballot, the Palmetto State's senior senator, Lindsey Graham, dropped out of the presidential race.
After breaking the news to his supporters on a Monday morning conference call, Graham made the announcement publicly in a video message Monday.
"I've hit a wall here," he first told CNN in an interview on "At this Hour." A staple of the undercard debates, Graham had been polling at the bottom of the GOP field, usually earning 1 percent or less in national polls.
Graham was one of four senators vying for the GOP nomination and the only one among them to have served in the military. The three-term senator retired from the Air Force Reserves earlier this year.
When he launched his campaign in June , Graham sounded prescient, vowing to wage a war on "radical Islam."
“I’m afraid some Americans have grown tired of fighting them. I have bad news to share with you — the radical Islamists are not tired of fighting you," Graham said back in June.
Since then, terrorist attacks in Paris and the mass shooting in San Bernardino, Calif., have shifted the tone of the election toward the national security issues Graham has long been vocal about. But as he's acknowledged, he's had trouble breaking through a field dominating by the aggressive posturing of Donald Trump and Texas Sen. Ted Cruz.
By comparison, Graham, a foreign policy hawk, emerged as a moderate voice within the party, knocking his competitors for alienating potential voters.
Speaking at the Republican Jewish Coalition's presidential forum earlier this month, Graham argued that he was the only kind of Republican who could win a general election and suggested that focusing on social issues and illegal immigration would doom the party.
“It’s not about turning out evangelical Christians, it’s about repairing the damage done by incredibly hateful rhetoric,” said Graham, who was a member of the so-called Gang of Eight senators who worked on bipartisan immigration reform in 2013.
Arizona Sen. John McCain, a loyal backer of Graham and his only Congressional endorsement , bemoaned the senator's departure from the crowded GOP field.
“With Senator Lindsey Graham’s announcement, Republicans lost our most qualified, thoughtful, fearless and honest presidential candidate, not to mention the candidate with the best (and it seemed sometimes the only) sense of humor," McCain said in a statement Monday.
McCain blamed the Republican National Committee's debate structure for denying Graham exposure.
“It is a pity that a bifurcated debate structure kept his voice and views from the wider public that needed to hear them," he said.
In suspending his campaign, though, Graham sounded optimistic that his foreign policy message was resonating.
"Four months ago at the very first debate, I said that any candidate who did not understand that we need more American troops on the ground in Iraq and Syria to defeat ISIL was not ready to be Commander in Chief," Graham said in his announcement video. "At the time, no one stepped forward to join me. Today, most of my fellow candidates have come to recognize this is what's needed to secure our homeland."
"I'm far more confident today that our party will reject the Obama doctrine of leading from behind and will provide the strong leadership America needs to restore our military and take the fight to our enemies and do what it takes to make our country safe and preserve our way of life," he said.
Florida Sen. Marco Rubio weighed in on Graham's departure from the race while in New Hampshire — the state where Graham had been focusing most of his campaign's efforts.
"We do not agree on everything on foreign policy, but he is a defender of a strong national defense as I am," Rubio said.
"I watched some of the debates he was in, some of the early debates, and I thought he was one of the most forceful voices on any of the debate stages about rebuilding our military. So we will miss that in the campaign, but I am sure he will continue to do that in his role in the Senate," Rubio added.
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