Nikki Haley loses Nevada's Republican primary despite no Donald Trump on ballot

Republican presidential candidate Nikki Haley embarassingly lost in Nevada's primary falling behind votes marked "none of these candidates" by Donald Trump supporters, Reuters reported citing findings of Edison Research.

Haley, the last remaining rival to Trump, was the only major Republican candidate contesting the party's Nevada primary on Tuesday as the former president was not on the ballot.

Meanwhile, US President Joe Biden won Nevada's Democratic presidential primary, securing 90% support with over 70% of votes counted.

As an incumbent, Biden faces minimal opposition within his party to run for re-election in a likely November general election rematch with Trump.

Trump will secure all of Nevada’s delegates in a separate caucus vote on Thursday, as he moves closer to clinching the nomination after back-to-back wins in Iowa and New Hampshire.

Trump did not compete in Tuesday's primary, which carried no weight in the Republican presidential nominating contest. Haley is not on the ballot in Thursday's caucus.

Republican voters could vote for "none of these candidates" in Tuesday's primary, and Haley has infuriated Trump by refusing to drop out of the contest.

With over two-thirds of the ballots counted, Haley had 32% of the votes, with "none of these candidates" at over 61% and the winner, according to Edison Research.

The Republican caucus, run by the Trump-friendly state party, is expected to win with only Trump on the ballot, ensuring his victory and all 26 delegates to the Republican National Convention in July.

Voters can participate in both the Republican primary on Tuesday and the Republican caucus on Thursday.