Former US Vice-President Mike Pence has officially filed paperwork to join an increasingly crowded field of Republicans running for president.

Mr Pence, 63, is set to formally launch his campaign with a video, speech and townhall event in the early voting state of Iowa on Wednesday.

The move pits him against Donald Trump, the man he served in the White House for four years from 2017-21.

The former president is currently polling well ahead in the race.

Most opinion polls show Mr Pence in a distant third place, with support in the low single digits.

The former Indiana governor and congressman is expected to position himself as a continuation of the Trump administration's conservative agenda, without the baggage.

Don’t think it’s going to work out for him

Good that he avoided the hangman's noose of Trump's thugs!