American President-elect Donald Trump is now just hours from claiming his place as leader of the free world - but New Zealand's own version of The Donald is keen to get in first.

Trump impersonator Alexander Sparrow will be marking the braggadocious tycoon's Washington DC inauguration with an hour-long show of his own in Wellington's Cavern Club tonight.

The 23-year-old actor was immersing himself in the hubristic Trump persona even before the incoming president won the Republican Party's nomination.

"He's a challenge to play, because everybody knows who he is - and if you're not doing a good job, it's obvious."


Fortunately, his sketch - complete with Queens accent, red tie, excessive hand gestures, generous self-congratulation - has proven a hit with reviewers, and even featured in the Wall Street Journal.

"I just took a punt and it really paid off.

"I've had reviewers who are anti-Trump say it's really good political satire, and I've had pro-Trump people come and just treat it as a roast."

Sparrow said he'd been impressed by the legion of other Trump impersonators around the world - notably Saturday Night Live's Alec Baldwin - but added his portrayal was set apart by his natural Trump-style hairdo.

"It's a good thing for the show, but it's a crap thing for me ... I'm stuck with it."

Meanwhile, a Kiwi in Washington DC described a "weird" atmosphere in the US capital amid the countdown to the inauguration, kicking off at 3am New Zealand time tomorrow.

"I think surreal is probably the right word," Sophia Duckor-Jones said.

She said hotels were full to the brim with Trump supporters and security had "at least tripled".

The event, expected to draw around 800,000 people, will be promptly followed by one of the largest demonstrations in US history, the Women's March on Washington with about 200,000 expected. Among 370 other marches around the world are Kiwi events being staged in Auckland, Wellington, Christchurch and Dunedin from 10.30am tomorrow.

Tensions between Trump supporters and opponents have been running high.

It was the same among expat Americans living here, said NZ American Association chair Larry Keim.

"It's a very sensitive subject for some people, but I think it's just a case of, let's get on with it and see how things go ... it's going to be an interesting four years, I'll say that much."

But Sparrow wasn't so sure Trump would only be around for one term.

"If the Democrats don't revitalise their campaigns and what they're about, then it's going to be eight years of Trump - and eight years of my show."