Lindsey Graham
Republican U.S. presidential candidate Senator Lindsey Graham speaks during the Republican presidential debate in Las Vegas, Nevada December 15, 2015.REUTERS/Mike Blake

South Carolina Senator Lindsey Graham has become the latest Republican presidential candidate to end his bid for the White House. The long-shot candidate announced his decision in a nearly two-minute-long video in which he told supporters he ran a campaign "you can be proud of."

Graham said he launched his campaign because the US must fight a war it "can't afford to lose". "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. "At that time, no one stepped forward to join me. Today, most of my fellow candidates have come to recognise this is what's needed to secure our homeland."

Despite being a favourite figure in the undercard debates, Graham never surpassed more than 1% in primary polls, The Washington Post reported. Graham did manage to gain the support of former presidential nominee, Arizona Senator John McCain. In a statement released after Graham's announcement, McCain said, "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 humour."

The Grand Old Party (GOP), however, is not suffering from a lack of candidates. Unlike the Democrats, which only has three candidates, the Republican Party is overflowing with contenders.

In the weeks leading up to the first primaries and the Iowa caucuses, there are other candidates who may be about to drop out. The Former New York Governor George Pataki, like Graham, has failed to crack 1% in the primary polls.

Also, the former Pennsylvania Senator Rick Santorum and former Arkansas Governor Mike Huckabee could also drop out of the race given their poor polling performances. Should those candidates drop out in the coming weeks, it is probable that the upcoming Republican debate would skip an undercard debate.