Latino voters are turning out in droves in the US presidential election, throwing down a huge challenge to Donald Trump and the Republican Party, according to US politics site, Politico.com.

Politico has reported that the early-vote returns from battleground states with large Hispanic populations are showing a record turnout.

It notes that Hispanics traditionally have a lower voter turnout than white or African-American voters.

The news site proposed that the strong Hispanic voter turnout had the potential to sink Mr Trump in a handful of states which were vital to him amassing the 270 electoral votes required.

Latinos in Nevada waited in line for 2 hours to vote. Republicans smell a conspiracy. https://t.co/SuMq6jhQfC

— Vox (@voxdotcom) November 6, 2016

In Nevada, the Latino turnout in early ballots propelled Democrats in Clark County — which takes in Las Vegas — to a lead of 72,000 which would be enough to secure the state for Ms Clinton, according to Nevada political analyst Jon Ralston, Politico reported.

The news prompted the Nevada GOP chairman Michael McDonald to claim the election was rigged.

“Last night, in Clark County, they kept a poll open till 10 o’clock at night so a certain group could vote,” Mr McDonald said at a Trump rally in Reno, Nevada.

“It wasn’t in an area that normally has high transition. The polls are supposed to close at 7 (pm).

“This was kept open till 10. Yeah, you feel free right now? Think this is a free or easy election?”

Mr Trump weighed in, too, at the same rally.

“Folks, it’s a rigged system. It’s a rigged system. And we’re going to beat it,” he said.

In Florida, Hispanics have so far cast about 14 per cent of the 5.7 million early and absentee ballots cast, putting them well beyond of their early voting results in 2012.

There are indications of similar stronger-than-usual turnouts in Arizona and Texas, Politico said.