In the run-up to the announcement at the party conference in Torquay, a seaside resort on Britain's south coast, there was an air of slight trepidation.
Paul Nuttall quit as UKIP leader after the general election, which saw UKIP's vote share shrink to 1.8% at the general election from 12.6% in 2015 - the year before the United Kingdom voted to leave the European Union.
Based in Folkestone, the former soldier and police officer was considered to be a front-runner in the contest and had seen the odds on him winning fall dramatically in recent weeks. In the 2005 general election he stood as the Lib Dem candidate against future Conservative chancellor Philip Hammond in the Runnymede and Weybridge constituency. But their new leader has promised to rally the party behind their core message of a guaranteed hard Brexit.
Ukip figures argue that the Prime Minister is heading for a deal which will let down the 3.9m people who backed the party in 2015 and millions more who voted Leave the following year.
Other contenders in the race were anti-Islam candidate Anne Marie Waters; the party's deputy leader Peter Whittle; London Assembly member David Kurten; MEP Jane Collins; Aidan Powlesland, and John Rees-Evans.
Asked at a press conference whether that fate had been averted by his victory, Bolton said, "Absolutely, yes". In the event Marie Waters won, Nigel Farage had threatened to set up a new party.
UKIP has no remaining MPs in the British parliament and lost all council seats bar one across the country in the last local elections.
The party has been riven by splits and disagreements, one of which resulted in MEP Steven Woolfe being taken to hospital after a fight with another Ukip MEP.
The protesters stood with banners reading: "We say no to racism". Instead he suffered a hefty defeat in February's Stoke-on-Trent Central by-election and later resigned after leading the party to a disastrous result in the snap general election.