New York, Feb 23

Vermont Senator Bernie Sanders has beat back a last-minute attack attempting to link him to Russia and won the Democratic Party's internal election in Nevada for the party's nomination in November's presidential election by a large margin.

Early results showed Sanders leading in the Saturday poll with about 40 per cent of the votes, far ahead of former Vice President Joe Biden trailing with about 22 per cent, and media tracking the polls declared him the winner.

The vote margin of victory now clearly marks him for now as the front-runner to challenge President Donald Trump, although 47 more states have yet to hold the intra-party elections his status could change.

The Washington Post reported on Friday that according to US intelligence officials Russia was trying to help the Sanders presidential campaign, and that the officials had briefed him about it a month ago.

The leak on the eve of the Nevada poll about a briefing from a month ago did not appear to impact the self-described democratic socialist Sanders, who had the support of a large number of minorities forming the party's steadfast base.

The Democratic Party establishment is obsessed with the Russian factor having blamed Moscow for the 2016 victory of Trump over Hillary Clinton and any mention of Moscow could turn off some voters.

Sanders disavowed Russian aid and said: "My message to (Russian President Vladimir) Putin is clear: Stay out of American elections, and as president I will make sure that you do."

Clinton had smeared Tulsi Gabbard, a Hindu-American seeking the party's presidential nomination, by calling her a Russian asset, and the latter has filed a $50 million defamation case against her.

The rise of Sanders has made the Democratic Party's establishment uneasy because they fear that his identification as a socialist will turn off moderate voters and lead to his defeat by Trump in a general election while dragging down party members of Congress.

Sanders, who is 78, has great appeal for younger voters because of his radical policies that include raising taxes on the rich and the minimum wage, and providing medical insurance, free college and free school meals for all.

Meanwhile, billionaire and former New York Mayor Michael Bloomberg has shot up in the national opinion polls, although as a late entrant he hasn't run in the three party elections so far.

He has made several racist and sexist comments and under his mayorship police followed a policy of stopping and searching young minority men randomly without case until a court banned it as unconstitutional, and could turn off many minorities and liberals.

The veteran politician has spent nearly $400 million from his estimated personal wealth of $62 billion in a media campaign using television ads and paid posters on social media and that has helped him get the third spot in the latest RealClear Politics (RCP) aggregation of national opinion polls with 15.2 per cent, while on one poll he came in second with 19 per cent.

Sanders leads in the RCP aggregation with 28.7 per cent and Biden has 17.3 per cent support.

He was initially considered the front-runner but has steadily slid in the polls, possibly damaged by revelations about his son's and his questionable actions in Ukraine that surfaced ironically during the Trump impeachment instigated by the Democrats to protect him.

A clearer picture of the candidates standing will emerge on March 3 when 14 states, including the big ones like California, Texas and Virginia, will hold the intra-party elections.

Bloomberg, who has been rising in the opinion polls, will be on the ballots for the first time.

Nevada was the first real test for the candidates because it is racially diverse, with whites constituting only 49 per cent of the population, unlike Iowa, where whites are 85 per cent, and Iowa that is 90 per cent white.

In those two states, former Mayor of South Bend, Indiana, Pete Buttigieg ran neck and neck with Sanders having an edge of a little over 1 per cent.

Buttigieg fell behind with only 18 per cent in the early results in Nevada.

Under the US system, party members or supporters elect the party's nominee for the general election.

The poll in Nevada was an open election, known as a caucus, in which party members go to the polling places and gather at designated spots for the candidate they support.

After an initial count, they are allowed to switch to other candidates and the final vote tally is made.

The caucuses there went smoothly, unlike in Iowa where a glitch in the phone app used to report the caucus results failed, delaying the announcement of the final tally and raising questions about its accuracy.

(Arul Louis can be contacted at arul.l@ians.in and followed on Twitter @arulouis)

Sanders wins Nevada Democratic presidential nomination election