March 8 (Bloomberg) -- Barack Obama is leading Hillary Clinton in Wyoming's Democratic caucuses today, according to an unofficial tally by the Associated Press.

With 87 percent of the precincts reporting, Obama, an Illinois senator, had 58 percent compared with 41 percent for Senator Clinton of New York. Clinton yesterday told reporters that Wyoming represented a ``steep uphill climb'' for her campaign.

The Wyoming vote is the first contest since the March 4 primaries in which Clinton, 60, revived her candidacy with wins in Rhode Island, Ohio and Texas. Wyoming has 12 pledged delegates at stake, awarded to the candidates proportionally based on the support they get in the caucuses.

The close Democratic nomination race brought both candidates to the state, the least populous in the U.S. and one that hasn't voted for a Democrat in a general election since 1964. Wyoming is the home state of Vice President Dick Cheney, a Republican.

Obama, 46, used the war in Iraq to draw his differences with Clinton and Republican presidential candidate John McCain. He responded to criticism from Clinton, saying she ``doesn't have standing'' to question his position.

``I don't want anybody here to be confused, I was opposed to this war in 2002,'' Obama told a crowd of about 1,200 people at the Casper Recreation Center yesterday. ``It was because of George Bush with an assist from Hillary Clinton and John McCain that we entered into this war.''

Newsweek Poll

Obama and Clinton are statistically tied nationwide for support among Democrats, according to a poll by Newsweek magazine released today. The poll shows 45 percent of Democrats and Democratic-leaning voters said they would most like to see Obama nominated for the presidency, compared with 44 percent who favored Clinton. The difference is well within the 5 percentage- point margin of error for Democrats in the survey.

Obama previously had a commanding lead in most national surveys. He yesterday accused Clinton of engaging in ``the politics of fear'' for running a television advertisement in Texas asking who voters would want answering the White House phone at 3 a.m. to respond to a crisis.

``That was designed to feed into your fears,'' Obama said. ``What do people think I'm going to do? I'm going to answer the phone, and I'm going to find out what's going on and I won't be browbeaten into watching a war that wasn't necessary, I will get all the information about what crisis is taking place.''

Obama's Foreign Policy

Clinton seized on comments made by one of Obama's top foreign policy advisers in an interview with the BBC. The adviser, Samantha Power, a professor of global leadership and public policy at Harvard's Kennedy School of Government, told the BBC that Obama's promise to withdraw all U.S. combat troops from Iraq within 16 months of taking office was a ``best-case scenario.''

The New York senator told reporters yesterday that she wasn't ``sure what the American people should believe'' on Obama's Iraq policy.

``While Senator Obama campaigns on his plan to end the war, his top advisers tell people abroad that he will not rely on his own plan should he become president,'' she said in Mississippi.

Power resigned yesterday because of comments she made in another overseas interview. She was quoted in the Scotsman newspaper as calling Clinton ``a monster'' who would do anything to win the nomination. Power issued a statement saying that her comment was ``inexcusable.''

Obama has 1,361 pledged delegates to the Democratic convention in August and Clinton has 1,220, according to an unofficial tally by the Associated Press. A candidate needs 2,025 to become the nominee, and neither Obama or Clinton is likely to have enough pledged delegates to secure the nomination before the Democratic convention in August.

To contact the reporter on this story: Kristin Jensen in Cheyenne, Wyoming at kjensen@bloomberg.netCatherine Larkin in Washington at clarkin4@bloomberg.net.

Last Updated: March 8, 2008 17:30 EST