From David Plouffe, Obama campaign manager (via Ben Smith):
“We are in terms of delegates ahead currently: about 606 to 534 in terms of pledged delegates awarded tonight,” he said.
The Obama campaign’s delegate guy, Jeff Berman, caught and corrected the inaccurate early reports of Nevada’s delegate count, so they’ve got credibility on this count.
On the other hand, Marc Ambinder has Clinton with 577 delegates and Obama with 460.
And a roundup of the states each candidate has won so far:
Obama – Georgia, Illinois, Delaware, Alabama, Utah, North Dakota, Connecticut, Kansas, Minnesota
Clinton – Oklahoma, Arkansas, Tennessee, New Jersey, New York, Massachusetts
McCain – Illinois, New York, New Jersey, Connecticut, Delaware, Oklahoma
Huckabee – West Virginia, Alabama, Arkansas, Georgia
Romney – Massachusetts, Utah