President Donald Trump was named the winner of the GOP’s Iowa caucuses in the least surprising result of the night.

As Trump’s Democratic rivals faced a tight race, the incumbent won the symbolic vote after running against former Massachusetts governor Bill Weld and Illinois rep Joe Walsh.

Team Trump headed to the state for the caucus with the President’s two sons Donald Jr and Eric holding a 'Keep Iowa Great' rally.

Insiders say the President’s re-election team saw the vote as a good opportunity to test the campaign’s organization ahead of the general election in November.

Donald Trump Jr, who was also joined by his girlfriend Kimberly Guilfoyle, mocked the left-wing swing of the Democratic Party to Bernie Sanders.

"When I see the ideals of socialism and communism actually being pushed — I know we say this as a joke and everyone's laughing, but it's not a joke," the 42-year-old said.

“While we've done a lot, there's still a lot left to be done. Donald Trump's gonna do that.”

The rally also included a speech from the president’s campaign manager, Brad Parscale, who told supporters: “We're here in force to show the American people that this is a real movement.”