Age: 44

Current role: Chairman of the Republican National Committee

Trump administration role: White House Chief of Staff

Mr Priebus has more than a decade of experience in Republican politics, and has been credited with bringing some major Republican figures, including Mr Trump's one-time foe Paul Ryan, onto the national stage.

He attended the University of Wisconsin–Whitewater, where he was president of the College Republicans, and later the University of Miami.

After starting out in law, he became the youngest chairman of the Wisconsin Republican Party in 2007. He was considered instrumental in guiding the state Republican party to success in the 2010 midterm elections, by uniting the burgeoning Tea Party movement with the mainstream.

Throughout the campaign, he was known for providing Mr Trump with a channel to Republican establishment, and for pressuring the party's big players to fall in line behind the nominee.

Steve Bannon