Barack Obama, the junior senator from Illinois, has generated enormous buzz in recent weeks as a possible presidential candidate, and "people are very, very excited about him as a great, up-and-coming Democratic personality,'' says Susie Buell, one of the country's leading Democratic donors and a loyal supporter of Hillary Clinton.

But on Obama as a presidential candidate, she says, "not now.''

"We are in a terrible time right now, between Iraq and global warming, and there's no messing around,'' says Buell, who -- along with her husband, Mark Buell -- has contributed more than $160,000 to Democratic causes since 2005. "It's not just about charisma, but about capability.''

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