At about the same time Edwards will endorse Obama, Clinton supporters on the Hill will try to get some attention holding an event to tout what they call her "strong pro-choice record."
It's a reminder that Obama has taken, not one, but two surprise endorsements. Not only is Edwards staging an endorsement just in time for the evening news, but the pro-abortion rights group, NARAL, endorsed Obama earlier Wednesday.
Clinton supporter Ellen Malcolm of EMILY'S LIST called that NARAL endorsement "tremendously disrespectful" of Clinton.
ABC News' Kate Snow, Raelyn Johnson, Eloise Harper, David Chalian, Sunlen Miller, Eric Johnson and Rick Klein contributed to this report.