Teterboro — Donald Trump announced a shake-up of his campaign leadership on Wednesday, the latest sign of tumult for his struggling White House bid less than three months from Election Day.The Republican nominee named Stephen Bannon of the conservative Breitbart News website as chief executive officer and promoted pollster Kellyanne Conway to campaign manager. The moves signal that Trump plans to embrace his populist, outsider persona in the campaign's final stretch rather than moderate and extend a hand to more traditional Republicans."I've known both of them for a long time. They're terrific people, they're winners, they're champs, and we need to win it," Trump said.Paul Manafort, Trump's controversial campaign chairperson, will retain his title, but it is unclear if his role will change. Manafort has spent months trying to ingratiate Trump to Republican lawmakers who have urged the billionaire businessman to dial back his fiery rhetoric and run a more traditional campaign.Trump has largely resisted those pleas and the latest staff changes seemed to guarantee he'll continue to maintain that posture.Bannon's website has been a cheerleader for Trump's campaign for months and also critical of Republican leaders. A former Goldman Sachs banker, Bannon does not have presidential campaign experience.‘Critical time’Conway joined Trump's campaign earlier this year as a senior adviser. A long-time Republican strategist and pollster, she has close ties to Trump's running mate, Indiana Govenor, Mike Pence.Conway said the moves were "an expansion at a critical time in the homestretch".Manafort deputy Rick Gates, who has been traveling often with Trump, is expected to maintain a senior role with the campaign.While Trump's campaign staff publicly insists there is plenty of time left for the Republican to change the trajectory of the race, the candidate is facing a shrinking timeline. Early voting begins in a handful of states in September.