WASHINGTON — Republican Sen. Lindsey Graham ended his 2016 campaign for president Monday, saying he remains committed to working to achieve security for the American people and helping the GOP expand its base.

With just over a month to go until voting begins, the South Carolina senator — the only candidate from one of the four early voting states — posted a video telling supporters “we have run a campaign we can be proud of.” He noted his emphasis on national security and improving the nation’s balance sheet, saying he “put forth bold and practical solutions to big problems.”

In a taped interview broadcast later on CNN, the senator warned that the election is “not about 2016” but instead “an election for the heart and soul of the Republican Party.” He warned that Donald Trump cannot defeat a Democrat like Hillary Clinton “without some major adjustments.”

Having mustered little support in the polls, Graham’s exit will not have an immediate effect on the race in the stretch before the Iowa caucuses and the New Hampshire primary.