FACTBOX: Profiles of U.S. presidential hopefuls

(Reuters) - Following are brief profiles of the three U.S. presidential contenders:

DEMOCRATS:

HILLARY CLINTON, 60, has nationwide name recognition as the wife of former President Bill Clinton. A senator from New York who would be the first woman president, Clinton revived her campaign by sweeping critical vote showdowns in Ohio, Texas and Pennsylvania after losing a string of contests to rival Barack Obama. Clinton's narrow victory in Indiana helped keep her campaign alive and she went on to score a big win in West Virginia. She faces an insurmountable lead in delegates to the nominating convention but has vowed to remain in the race until the last Democratic primaries are concluded. Clinton has focused recent campaign efforts on her national security experience and emphasizes efforts to insure 47 million Americans without health insurance. She has criticized Obama for not having enough experience to lead the nation.

BARACK OBAMA, 46, had appeared headed for victory after his long winning streak until the losses in Ohio and Pennsylvania. But he regained momentum with a decisive win in North Carolina last week. Due to the way delegates are awarded for the Democrats, Obama has moved ahead of Clinton in the overall delegate count. He has more superdelegates and a larger share of the popular vote. Obama, who would be the first black president, gained national recognition when he gave the keynote address at the 2004 Democratic convention before he was elected to the U.S. Senate, representing Illinois. Obama has opposed the Iraq war from the beginning and portrays himself as a Washington outsider who has attracted huge campaign crowds cheering his message of the need for change in the country.

REPUBLICAN:

JOHN MCCAIN, 71, a senator from Arizona, clinched the Republican nomination after four big victories on March 4. The wins forced his last major rival, former Arkansas Gov. Mike Huckabee, out of the race and gave McCain more than the 1,191 delegates needed to win the nomination. The U.S. Naval Academy graduate and Navy pilot spent 5 1/2 years as a prisoner of war in Vietnam. McCain, who turns 72 in August, would be the oldest first-term president. He has been a pro-business conservative and abortion foe, while supporting the Iraq war and calling for extra troops to quell the violence. He says he has the best national security credentials of any of the presidential hopefuls.

(Writing by Deborah Charles; Editing by Chris Wilson)

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