Since his resignation following the EU referendum in June, Farage has ridden the wave of his campaign's success to the United States where he emerged as a keen ally of President-elect Donald Trump.
But his UK Independence Party has been reeling from internal crises, including high-profile resignations, claims of misappropriated EU funds and a fight between two its European Parliament lawmakers.
Three candidates are now competing for the leadership - former deputy leader Paul Nuttall, former deputy chairman Suzanne Evans and party activist John Rees-Evans - with the winner to be announced on November 28 after a vote by party members.
Nuttall, an MEP and firm favourite for the job, has pledged to "unite the party" if elected, demanding an end to "infighting and squabbling".
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Evans, a former BBC radio reporter deemed his closest challenger, says the party must broaden its appeal to include women and minorities, in order to win seats in parliament.
Meanwhile, the candidacy of businessman Rees-Evans, a former soldier, has been largely overshadowed by his calls to bring back the death penalty for paedophiles.
The leadership vote follows the resignation in October of Farage's successor Diane James after only 18 days in the job and her subsequent departure from the party on November 21.
The favourite to replace her, Steven Woolfe, quit in October following an altercation with a fellow MEP at the European Parliament that left him hospitalised - a further embarrassment for UKIP.
"I have come to the conclusion that UKIP is ungovernable without Nigel Farage leading it and the referendum cause to unite it," Woolfe said in a statement published online.
Farage stepped into the breach as interim leader after James's resignation but ruled out returning longer-term, having achieved his life mission when Britain voted to leave the EU on June 23.