How to watch Nevada's Democratic Caucus

On Saturday, Nevada voters will show up to caucus sites across the state to express support for their preferred candidate in the third Democratic nominating contest for president.

Voters can choose from Hillary Clinton and Bernie Sanders. Former Maryland Gov. Martin O'Malley suspended his bid after the Iowa caucuses earlier this month. The state's Republican caucuses will be held on Tuesday.

Watch CBSN for coverage of Nevada's Democratic caucuses

Caucusing officially begins at 3 p.m. ET when Democrats will be sorting themselves into their candidate preference groups. They will move to different sides of the room to show which candidate they support.

Nevada has 43 delegates in total, but 20 are superdelegates, 8 of which are unpledged and 12 are pledged already. The remaining 23 delegates will be up for grabs on Saturday. Delegates are awarded based on the tallies in the caucuses and the number of delegates up for grabs at each of the caucuses. The winner will be the candidate who wins the largest amount of delegates.

While the state operates under a closed caucus system in which there are separate caucuses for each political party, and doesn't allow independents to participate, a quirk in the system could allow Republicans to participate in the Democratic caucus. According to Nevada-based journalist Jon Ralston, registration for Republicans closed on Feb. 13, but Democrats are permitting same-day registration on Saturday. As a result, he says Republicans could show up to caucus Saturday, register as Democrats, but it wouldn't show up in the Republican voter rolls.

The caucuses come as Clinton and Sanders have fought for the support of Hispanic voters in the state and the support of black voters in South Carolina, which holds its Democratic primary on Feb. 23.

A CNN/ORC survey released Wednesday showed that the race in Nevada had tightened with 48 percent supporting Clinton and 47 percent backing Sanders. A CBS News national poll released Thursday, meanwhile, found 47 percent of Democrats across the U.S. back Clinton while 39 percent support Sanders. Ten percent said they are undecided.

At a town hall hosted by MSNBC Thursday night, Clinton questioned the authenticity of Sanders' identity as a Democrat.

"Maybe it's that Senator Sanders wasn't really a Democrat until he decided to run for president. He doesn't know what the last two Democratic presidents did," she said.

Earlier on Thursday, Sanders called some of President Bill Clinton's achievements "disastrous" but attempted to re-characterize that description at the town hall.

After Nevada, both candidates will have a week to campaign in South Carolina. Influential South Carolina Democrat Rep. James Clyburn announced Friday that he is endorsing Clinton. Actor Morgan Freeman has recorded a new ad for Clinton about her lifetime commitment to breaking barriers for Americans. It will air over the weekend in South Carolina and nationally.