Ron DeSantis used a fake Winston Churchill quote as he signed off on his ill-fated presidential bid and endorsed Donald Trump as the Republican nominee for the White House.

The Florida governor, 45, announced his decision to pull out of the race on Sunday in a video posted on social media accompanied by the phrase: “Success is not final, failure is not fatal: it is the courage to continue that counts.”

Mr DeSantis attributed the quote to Mr Churchill, but historians have repeatedly disproved the notion it was ever uttered by the former British prime minister.

The website of the International Churchill Society states: “This fake quote is very often attributed to Churchill but appears nowhere in the Churchill canon.”

The society’s view is supported by Richard Langworth, an historian and the author of 11 books on the wartime leader.

“While included in some poorly researched quote books,” he wrote in 2011, the quote can’t “be found among Churchill’s 50 million published books, articles, speeches and papers; and words about him by close colleagues”.

“Based on editing the 4,000 quotes in Churchill by himself, I don’t believe it sounds like his prose,” Mr Langworth added.

Mr DeSantis’s decision to end his bid for the presidency follows a lacklustre campaign punctuated by frequent gaffes and a string of embarrassing moments.

Only a few hours before the post with the fake quote by Mr Churchill, his campaign chief had faced criticism for spending too much time working on a 1,000-word jigsaw puzzle in the run-up to the Iowa caucuses, which saw Mr DeSantis finish a distant second to Mr Trump.

The Florida governor was also mocked for supposedly wearing height-increasing lifts in his cowboy boots.

His run for the Republican nomination began in inauspicious circumstances last May, when the launch of his campaign on X, formerly known as Twitter, was marred by a series of technical glitches as he appeared alongside owner Elon Musk.