Hillary Clinton has won Nevada's Democratic Party caucuses in a hard-fought race against second-place candidate Barack Obama. Mike O'Sullivan reports from Las Vegas, Mitt Romney easily won the Republican race in Nevada.

 New York Senator Clinton won the popular vote by 51 to 45 percent (over Barack Obama), which gives her momentum as she heads into future races. Former senator John Edwards placed a distant third.

Former Massachusetts governor Mitt Romney gained an easy win in the Republican caucuses, finishing nearly 40 percent ahead of his closest rivals. Romney campaigned heavily in the state and dominated the race against Arizona senator John McCain and Texas congressman Ron Paul.

The Democratic race was hard fought. Illinois Senator Barack Obama had the backing of the powerful Culinary Workers Union, whose members work in hotels, restaurants and casinos. But Senator Clinton had backing from other labor groups, including the teacher's union.

A mixed group of 400 hotel and casino workers came to a Democratic caucus in the entertainment district called the Las Vegas Strip, one of nine special sites set up in the district.

Caucus goers chanted their support of rival candidates before the selection started.

Then they gathered in different parts of the room, according to candidate, to make their choices known.

Hotel worker Tanya Friis, like the majority at her caucus, supported Clinton.

"To me, it's a very important election that I feel passionately about, and I just could not live with myself if I didn't participate," said Friis.

For Democrats, Nevada was a test of the candidates' appeal to Hispanics, who make up nearly one quarter of the state's population and 12 percent of the electorate. The powerful union that backed Obama is more than 40 percent Hispanic, but Clinton also received endorsements from several Hispanic leaders. An Associated Press poll of caucus goers shows she did well among Hispanics, and with whites and women voters. Obama got strong support from African Americans.

Religion played a role in the Republican caucuses. One in four who took part was Mormon, as is the winner, Mitt Romney.

Republicans said their number one concern is the economy. Romney, a millionaire businessman, says is well positioned to deal with that and other issues.

"People are very concerned about what is happening globally, but they are also concerned about what is happening here at home, and they want to know how our economy is going to be strengthened, both short term and long term," said Romney.

Democrats will hold their next contest in South Carolina Saturday, and Republicans are focusing on the Florida primary three days later. Both parties are looking ahead to Super Tuesday on February 5, when more than 20 states will hold primaries and caucuses.