Sanders had a formidable lead, taking 46.6 per cent of the delegates with 22 per cent of precincts reporting.

'I'm delighted to bring you some very good news,' a jovial Sanders announced to a crowd of supporters at his rally in San Antonio, Texas Saturday evening, alongside his wife Jane. 

'I think all of you know we won the popular vote in Iowa. We won the New Hampshire primary. And, according to three networks and the AP, we have now won the Nevada caucus,' Sanders said as audience members erupted in chants and cheers. 

Sanders then predicted he would go on to 'sweep' the primary elections in the rest of the states.   

Trump went ahead and congratulated Sanders before most networks had called the race. 

'Looks like Crazy Bernie is doing well in the Great State of Nevada. Biden & the rest look weak, & no way Mini Mike can restart his campaign after the worst debate performance in the history of Presidential Debates,' Trump said. 

'Congratulations Bernie, & don't let them take it away from you!' the president wrote.  

In response to the president's tweet, Sanders told rally-goers not to reveal how much support he had in the country's most populous red state.