If you ever wondered how Donald Trump managed to get as far as he did in the race to the White House, you can be assured you're not alone.

Few people thought the colourful tycoon had a chance of becoming the Republican nominee, let alone the president. How did he get so far?

People voted him there, obviously. But not nearly as many as you'd think.

A group of women hold a sign as they wait to attend a campaign rally for Trump. Photo / AP
A group of women hold a sign as they wait to attend a campaign rally for Trump. Photo / AP

The New York Times revealed last month that only 9 per cent of Americans actually voted for either Trump or his Democratic rival, Hillary Clinton, in their respective parties' nominating contests.


And here's why.

There are 323 million people living in the United States. Almost a third of them (103 million) aren't eligible to vote, and 88 million don't vote even though they can. Another 73 million people chose not to vote in the primaries - you can expect them to pop up in the general election.

That leaves 59 million people who did vote in the primaries, with around half of that total going to each party. Once you discount the votes that went to Trump and Clinton's rivals, the numbers are stark: Trump received 14 million primary votes, and Clinton earnt 17 million.

Put another way, Trump was elected the Republican nominee by just 4.3 per cent of America's population.

The US always does things bigger, and probably stranger, than many Australians may be used to - take the primary process and Trump's nomination.

Each state has a certain number of "delegates", who are assigned to each candidate based on his share of the vote. To become the Republican nominee, one candidate eventually needs to win 1237 of these delegates.

Trump hit that number, clinching the nomination.

According to Dr David Smith, a senior lecturer in American Politics and Foreign Policy and academic director of the United States Studies Centre at the University of Sydney, not all Republicans wanted Trump as the nominee.

Then again, clearly not all Democrats wanted Clinton either.

But just like most things in life, it comes down to money and power, and those who voted Trump and Clinton in would have been among the most staunch Democrats and Republicans.

"In the US presidential system, the president is separate to the legislature, unlike our PM," he said. "In Australia parliament is more cohesive and plays a bigger role in determining who runs."

Dr Smith said it was up to the president to fund their own campaign and every member of the legislature had to run their own campaign.

Voting also isn't compulsory, which meant those who did vote in the primaries were among the most politically vocal.

"These people are the hardcore believers of the party," Dr Smith said. "The rules in the primaries are complicated. The US has a bigger system with a lot more money."

He said the trick in the primaries was for nominees to appease and appeal to that hardcore party base, something both Clinton and Trump had to do.

That explains why Trump has massive appeal with the conservative Republican base.

"Hillary Clinton was up against Bernie Sanders who had enormous support of the left," Dr Smith said. "In order to win that nomination she had to go more left that she wanted.

"Trump appealed to that hardcore Republican base with his stance on Mexico."

But while Clinton is now moving back towards the centre to appeal more to the broader US public, her rival isn't doing the same.

"Trump has no idea how to appeal beyond the (hardcore) party base," he said. "Clinton spent more time trying to win back the trust of the Democrats, but a lot of people on the left still don't trust her.

"She is consolidating support more which has been helped by the (presidential) debate and most Democrats would still prefer her over Trump."