Voters in the Western state of Nevada are taking part in party caucuses Saturday to help choose the nominees for U.S. president. Mike O'Sullivan has a preview from Las Vegas on the first-in-the-West presidential polling.

For both major parties, the race is competitive this year, says Nevada Republican spokesman Steve Wark.

"This is the very first time since 1926 that a sitting president or vice president has not been running for the nomination in either one of the two parties. And so it's a wide open, fluid landscape that both parties are playing on," he said.

On the Democratic side, a poll by the Las Vegas Review-Journal, released Friday, showed Senator Hillary Clinton with a nine point lead over Senator Barack Obama, with former Senator John Edwards in third place.

Among Republicans, the poll showed former Massachusetts Governor Mitt Romney leading Senator John McCain by 15 points. Former Arkansas governor Mike Huckabee was in third place.

This year's Nevada caucuses have taken on added importance in the national race because of their timing. With help from a Nevadan who is U.S. senate majority leader, Senator Harry Reid, the Democratic Party advanced its caucuses to January, making them among the first in the nation. Republicans followed suit and are also holding their caucuses Saturday.

Democrat Kirsten Searer says Nevada's diversity makes the state's vote important for her party.

"This is the first real test of the minority communities amongst these presidential candidates," said Searer. "Nevada has almost 40 percent minority population, largely Hispanic population."

Sylvia Scott is part of that minority population. An African-American, she moved here with her family from Chicago, the home of Democratic candidate Barack Obama. She likes his stand on the issues, especially on the environment, and plans to attend a caucus to support him.

"It's exciting to us. Yes. [We're] looking forward to change," she said.

Participation in the Nevada caucuses has historically been low. For the Democrats, the turnout grew to 9,000 in 2004. With all the attention focused on this year's caucuses, Democratic Party officials expect a turnout as high as 40,000.

Voters in many states voice their preference for nominees in primary elections. A caucus is less formal. Democratic Party official Kirsten Searer says it is simply a meeting of neighbors.

"And instead of casting ballots, you elect delegates in favor of the candidate that you like," said Searer. "For example, my home precinct has eight delegates. And what happens is they say, OK, if you are [for] candidate A, you go in this corner; if you're for candidate B, you go in that corner. And you count heads. One candidate might get four of those delegates."

Or three delegates, or five, or none.

The Nevada Republican party has a similar process, but their caucus voters cast secret ballots.

Democrats who are working Saturday in the entertainment district can attend special caucuses set up by their party in casinos. Some supporters of Democratic candidate Hillary Clinton challenged the plan in court after unions for hotel and casino workers endorsed Barack Obama. A federal judge rejected the lawsuit, allowing the special caucuses on Saturday.

Steve Wark says a competitive race has generated interest, and most voters expected to take part in these caucuses have never done it before.

"Nevada is totally wide open. It's wide open to all the candidates, and it's going to be a tremendous learning experience for thousands of people," he said.

Democrat Kirsten Searer adds that Nevada's caucuses are the first test in the West in this election year, and the country is watching.