According to the Obama campaign's internal delegate countdown, the senator needs 35.5 delegate pledges to clinch the nomination. The number does not include Rep. John Spratt, whose endorsement will come shortly, according to Rep. James Clyburn and Rep. Tim Moore, who is expected to endorse Obama later in the day.

Obama deputy communications director Dan Pfeiffer's index finger will be swollen with all the endorsement e-mails he's going to have to send today.

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