UPDATE: The Post confirms it.
MORE UPDATES FROM JOHN: The Times made me laugh:
Officials announced the news shortly after Mr. Obama landed here late this afternoon. The campaign has timed the announcement to coincide with the start of the major evening newscasts, which would have otherwise focused on Senator Hillary Clinton’s landslide victory in West Virginia, which raised new questions about Mr. Obama’s strength with white working class voters.Lots of buzz on the internets about a big endorsement for Obama tonight. Via Taegan Goddard:
Sen. Barack Obama's campaign is planning to announce "a major endorsement" tonight at 6:30 pm ET.We've heard it from good source that it will be John Edwards.
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