FACTBOX - Profiles of U.S. presidential hopefuls

(Reuters) - Leading candidates in the race for the November 2008 U.S. presidential election head into a new round of primary elections and caucuses this week in Michigan, Nevada and South Carolina.

Following are brief profiles of the main contenders:

DEMOCRATS:

HILLARY CLINTON, 60, faces another showdown with rival Barack Obama on January 19 in Nevada, where Obama secured the support of the state's most powerful labour union. Clinton, a senator from New York, would be the first woman U.S. president if elected. A former first lady, she has emphasized efforts to insure 47 million Americans without health coverage and criticized opponents for lack of experience. After a disappointing third-place finish in Iowa, Clinton bounced back to a surprise win in New Hampshire. Her once strong lead in national opinion polls has narrowed.

JOHN EDWARDS, 54, is focused on winning the January 26 Democratic primary in South Carolina, the state where he was born and where he won the primary during his unsuccessful 2004presidential bid. He also is hoping to pull in labour votes in Nevada, where a recent poll showed him only narrowly trailing Obama and Clinton. The former senator from North Carolina was the Democratic nominee for vice president in 2004. He has made combating poverty a major campaign theme and called his vote to authorize military action in Iraq a mistake. Edwards now urges withdrawal of U.S. troops from Iraq. He edged out Clinton for second place in Iowa but came in third in New Hampshire and trails Obama and Clinton in national polls. His wife, Elizabeth, is being treated for a recurrence of cancer.

BARACK OBAMA, 46, hopes Nevada will be a repeat of his first-place showing in Iowa's caucuses. The first-term Illinois senator, seeking to become the first black president, won the support of Nevada's powerful Culinary Union, which has 60,000 members. Obama gave the keynote address at the 2004 Democratic convention before he was elected to the Senate. He has opposed the Iraq war from the beginning and has tried to cast himself as a Washington outsider. He scored a surprise victory in Iowa and came in second to Clinton in New Hampshire.

REPUBLICANS:

RUDY GIULIANI, 63, was once the party's frontrunner but is fighting to stay alive in the coming votes. The former New York mayor, who has made his leadership during the September 11 attacks a centrepiece of his candidacy, did not campaign heavily in the states holding the early contests. He focused instead on the larger states that vote later, particularly Florida. Widely shunned by many conservatives because of his support for abortion rights, gun control and gay rights, he received the endorsement of Christian evangelist Pat Robertson.

MIKE HUCKABEE, 52, a Baptist minister, hopes to win support from the large bloc of evangelicals in the January 19 vote in South Carolina. The bass-playing former Arkansas governor was born in Hope, Arkansas -- the birthplace of Bill Clinton. He won the Iowa caucus thanks to strong support from fellow evangelicals, who admire his religious beliefs and conservative stances on issues like abortion and gay marriage. Known for his wit, he has been criticized for a lack of knowledge on foreign policy.

JOHN MCCAIN, 71, who lost the South Carolina primary in a bitter battle with George W. Bush during his run for president in 2000, hopes to win over the state's sizable population of military veterans on January 19. He also is looking for a win in Michigan, a state he won in 2000. The senator from Arizona attended the U.S. Naval Academy and was shot down in 1967 over Vietnam, where he spent 5 1/2 years as a prisoner of war. He would be the oldest first-term president, at 72, if elected. He has been a pro-business conservative and abortion foe while supporting the Iraq war and calling for additional troops to quell the violence. His campaign was running low on cash and hit by a wave of defections this summer but he rebounded with a big win in New Hampshire.

MITT ROMNEY, 60, needs a win in his native Michigan to keep his White House hopes alive after second-place finishes in Iowa and New Hampshire. The Harvard-educated former Massachusetts governor was previously a business executive who co-founded the private equity firm Bain Capital. He has appealed to conservatives with his opposition to gay rights and abortion rights, which he once supported. Romney, whose father was once Michigan governor and an auto executive who sought the Republican presidential nomination in 1968, would be the first Mormon president.

(Writing by Deborah Charles, Jeremy Pelofsky, Paul Grant and Andy Sullivan in Washington; Editing by Bill Trott)

(To read more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at blogs.reuters.com/trail08/)