Clinton wins Kentucky, Obama seeks milestone

WASHINGTON (Reuters) - Hillary Clinton captured the first of two Democratic nominating tests on Tuesday with a big win in Kentucky, but rival Barack Obama was looking for an Oregon victory later in the evening that would help him reach a major milestone in the race.

Clinton was headed to a double-digit margin in Kentucky, a bastion of the white working-class voters who have been her biggest supporters. But the results there and in Oregon will give Obama a majority of pledged delegates won in the lengthy state-by-state nominating fight with Clinton.

Obama hopes that landmark signals the beginning of the end of their grueling Democratic race to contest November's presidential election against Republican John McCain.

The Illinois senator will still be about 50 delegates short of the 2,026 needed to win the nomination at the Democratic convention in August, but he hopes the milestone will send more undecided superdelegates -- party officials who can back any candidate -- flooding his way.

Obama, who would be the first black U.S. president, contends those superdelegates, who have been moving his way heavily in recent weeks, should support him because he won the most delegates in state voting.

Clinton, who has ignored Obama's almost unassailable lead in delegates for weeks and shrugged off calls to quit the race before the last of the primary elections on June 3, has vowed to keep campaigning.

She says superdelegates should reconsider their decisions because she would be a stronger opponent for McCain, an Arizona senator. Her victories in big states like Pennsylvania and Ohio gave her a broader base of support than Obama, she said.

Oregon's balloting ends at 8 p.m. PDT/11 p.m. EDT (0300 GMT on Wednesday) Results are expected shortly after.

Oregon and Kentucky have a combined 103 delegates at stake. After Tuesday, only three contests remain, with 86 delegates at stake.

Obama will celebrate Tuesday's returns at a rally in Iowa, a general election battleground where he made his breakthrough with a big win in the first Democratic contest on January 3.

A delegate count by MSNBC gives Obama 1,917 delegates to Clinton's 1,725.

Clinton, who would be the first woman U.S. president, visited a Kentucky restaurant with her husband, former President Bill Clinton, to encourage voters to turn out on Tuesday. She will hold an evening rally in Louisville to await returns.

"I think it's likely we'll be able to unite the party and win in November," Bill Clinton told reporters. "We have more voters, more workers, more givers than ever before, but the energy is on our side and the issues are on our side."

Geraldine Ferraro, a New York Democrat who in 1984 became the country's first woman vice presidential candidate of a major party, said on NBC's "Today" show that Clinton was the victim of sexist campaigning.

"Latent sexism has been around this country for a long time, in this campaign it was patent," Ferraro said.

(Additional reporting by Jeff Mason and Ellen Wulfhorst; Editing by Doina Chiacu)

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