WASHINGTON -- Hillary Rodham Clinton needed a game changer. Instead, it's almost game over.

Barack Obama won a resounding victory in North Carolina after the worst two-week stretch in his campaign. And Clinton, fueled by a burst of energy from her convincing win in Pennsylvania last month, barely eked out a win in Indiana despite her full-throated populist appeal in that largely blue-collar state.

There are six primaries left in the Democrats' epic battle for the nomination, but Tuesday's results were decisive on their own: They offered Clinton her last, best chance to turn the tables on her rival, and she didn't even come close.

"It's bad news for Hillary Clinton, but frankly I think the game changed a long time ago," said unaligned Democratic strategist Garry South. "Barack Obama has outraised her substantially, he's won more states, more pledged delegates, and is ahead in the popular vote. It's obvious he's outperformed her."

Indeed, Obama managed to outpace Clinton through a period that tested his mettle and political skills more than any other in the 15-month campaign. In a stretch that pitted Clinton's gritty determination against Obama's calm fortitude, the Illinois senator prevailed.

To be sure, Obama is still struggling to win some demographic groups, notably blue-collar white voters, who are a key component of the Democratic base.

Among whites without college degrees, Clinton outdid Obama by 64 percent to 35 percent in Indiana, and 71 percent to 26 percent in North Carolina. The New York senator and her surrogates have trumpeted that advantage, hoping to persuade the so-called superdelegates likely to decide the race that she would be the stronger Democratic candidate in the general election.

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