WASHINGTON Barack Obama beat rival Hillary Clinton in North Carolina on Tuesday, moving a step closer to securing the Democratic presidential nomination after a grueling struggle.
Clinton led Obama in early returns in Indiana as the two Democrats, who have been locked in a see-saw battle for months, appeared headed to a split of the two states.
The New York senator was ahead of Obama by 57 percent to 43 percent with about 18 percent of votes counted in Indiana.
The two states, with a combined 187 delegates to the August nominating convention at stake, were the biggest prizes left in the race to pick the party's presidential candidate for November's election. After Tuesday, only six contests remain.
A pair of losses would be disastrous for Clinton, the former first lady who is struggling to overtake Obama in the White House race.
Obama, an Illinois senator, has an almost unassailable lead in pledged delegates who will help select the Democratic nominee to face Republican John McCain in November.
If Obama wins in both Indiana and North Carolina, it would end Clinton's slender hopes of catching him in either delegates or popular votes won in the nomination battle and spark renewed calls for her to step aside.
A split decision in Tuesday's contests would leave the race largely unchanged before the last six contests, with 217 delegates at stake.
But neither candidate can win enough delegates to clinch the race before the state-by-state voting ends on June 3, leaving the decision to the nearly 800 superdelegates -- party insiders free to back any candidate at the Democrats' nominating convention in August.
Exit polls showed the economy was the top issue for two-thirds of Indiana voters and about 6 of every 10 voters in North Carolina. Clinton, who would be the first woman U.S. president, narrowly led among those voters in Indiana, while Obama led in North Carolina.
Obama, who would be the first black U.S. president, won 9 out of 10 black voters in North Carolina, who made up about one third of the state's primary voters, exit polls showed.
(Additional reporting by Caren Bohan and Jeff Mason; Editing by Frances Kerry)
(To read more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at http:/blogs.reuters.com/trail08/ )