JOE Biden is to become the 46th president of the United States after winning the race to the White House by defeating Donald Trump.

It has been a tense few days since Tuesday’s election waiting for votes to be counted in several key states, but it is now projected Biden has won the vital battleground of Pennsylvania, propelling him over the 270 electoral college votes threshold required to clinch victory.

Biden has 273 college votes to Trump’s 214, but the Trump campaign has indicated their candidate does not plan to concede, and the result will be subject to legal challenges.

Biden, who will be sworn into office in January, said it was now time for America to "unite and heal".

"With the campaign over, it’s time to put the anger and the harsh rhetoric behind us and come together as a nation," he said.

He added he was "honoured and humbled" to be elected and said the record turnout in the face of "unprecedented obstacles" showed that democracy "beats deep in the heart of America".

The result makes Mr Trump the first one-term president since the 1990s.

Mr Biden’s running mate, Kamala Harris, is set to become the first woman vice-president.

The election has seen the highest turnout since 1900. Mr Biden has won more than 74 million votes so far, the most ever for a US presidential candidate. Mr Trump has drawn more than 70 million, the second-highest tally in history.The 77-year-old Biden will become the oldest US president.