Democrats flocked to caucus sites across Nevada Saturday, deciding a contest that could offer the first glimpse of whether Bernie Sanders can broaden his voter base and chip away at Hillary Clinton’s expected hold on minority voters.

The early vote count, as well as polls of voters arriving at the caucuses, suggested a close race between the Democratic rivals. About two-thirds of voters said they were attending the caucuses for the first time, and they were slightly more likely to support Sanders.

"If there’s a large turnout I think we’re going to do just fine," Sanders told reporters in Las Vegas. "If it’s a low turnout. That may be another story."

The polling was conducted for AP and the television networks by Edison Research as voters arrived at 25 randomly selected sites.

Nevada was the first of two presidential primary contests being held Saturday. Republicans were battling in South Carolina, a state seen as billionaire Donald Trump’s to lose and one that could start to clarify who, if any, of the more mainstream candidates might emerge to challenge him.

For both parties, the 2016 election has laid bare voters’ frustration with Washington and the influence of big money in the political system. The public mood has upended the usual political order, giving Sanders and Trump openings while leaving more traditional candidates scrambling to find their footing.

No candidate has shaken the establishment more than Trump. The billionaire businessman spent the week threatening one rival with a lawsuit, accusing former President George W. Bush of lying, and even tangling with Pope Francis on immigration.

The prospect of a Trump win alarmed rival Jeb Bush, the former Florida governor trying mightily for a strong showing in the first Southern state to vote.

"Trump can’t win, plain and simple," Bush told reporters outside a polling place in Greenville. "This isn’t about appealing to people’s deep anxiety. … He can’t be president. A ton of people would be very uncomfortable with his divisive language and with his inexperience in so many ways."

A Trump victory could foreshadow a solid performance in the collection of Southern states that vote on March 1. Victories in those Super Tuesday contests could put the billionaire in a commanding position in the delegate count, which determines the nomination.

Texas Sen. Ted Cruz banked on a well-regarded get-out-the-vote operation and 10,000 volunteers to help overtake Trump on Saturday, as well as in the Southern states that follow.

A failure to top Trump in South Carolina could puncture that strategy, though Cruz, who sidetracked briefly to Washington to attend the late Supreme Court Justice Antonin Scalia’s funeral Mass, will still have more than enough money to run a long campaign.

Marco Rubio and Bush were fighting to establish themselves as credible alternatives to Trump and Cruz, candidates some GOP leaders believe are unelectable in November.

Neither Bush nor Rubio expected to win South Carolina. But they wanted to finish ahead of one another; otherwise, there would be tough questions about long-term viability.

Rubio scored the endorsements of several prominent South Carolina politicians, including Gov. Nikki Haley, and seemed to have rebounded after a dismal debate performance two weeks ago.

Teacher Jason Sims of Mount Pleasant went for Rubio in a last-minute decision and said Haley’s announcement was "a big deal."

"I was kind of riding the fence," Sims said. "I trust her."

Bush hoped his deep family ties to South Carolina — his brother and father each won two primaries here — would be a lifeline for his struggling campaign.

Also in the mix was Ohio Gov. John Kasich, who had low expectations in South Carolina. He was looking toward more moderate states that vote later in March. Retired neurosurgeon Ben Carson had a small but loyal cadre of followers.

For Democrats, the contest between Clinton and Sanders has grown closer than almost anyone expected.

Sanders, a self-proclaimed democratic socialist, has energized voters, particularly young people, with his impassioned calls for breaking up Wall Street banks and providing free tuition at public colleges and universities.

Clinton hoped to offset Sanders’ youth support by winning big majorities among blacks and Hispanics. She eyed Nevada, where one-fourth of the population is Hispanic, as the first in a series of contests that would highlight that strength.

But Clinton’s campaign has played down expectations in Nevada in recent days.

A victory for Sanders — or even a narrow loss to Clinton — would give his campaign a boost heading into the Democratic contests on Super Tuesday.

According to the early entrance polls, Clinton captured the support of voters for whom electability and experience were of paramount importance. Sanders did best with voters who were looking for a candidate who cares and is honest.

Democrats and Republicans will swap locations in the coming days. The GOP holds its caucus in Nevada on Tuesday, while Democrats face off in South Carolina on Feb. 27.

(Copyright (c) 2016 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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