A few months later, as his presidential campaign fizzled, Graham called Trump a "race-baiting, xenophobic, religious bigot".

That criticism would reach a crescendo in his famous Twitter post in May 2016 that if the Republican Party chose Trump as its nominee it "will get destroyed ... and we will deserve it".

Graham – like many national Republicans – stayed wary of Trump during his 2016 general election race against Hillary Clinton. He publicly announced he would not vote for either, instead opting for independent candidate Evan McMullin.

Once Trump secured victory, however, Graham changed his attitude.

As Trump consolidated his control over the Republican Party during his first presidential term, Graham became a close ally and, by all accounts, a friend.

The two men regularly golfed together, and the senator, who was always a fixture on cable news television, ardently defended the president and his policies.

When Trump picked Brett Kavanaugh to be his second Supreme Court appointment, Graham angrily condemned allegations of sexual assault made against the nominee, who denied wrongdoing. Through his intervention, Graham helped to ensure he was confirmed – albeit by the narrowest of margins.

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