ABC News is reporting that Hillary will drop out of the race Friday.
The ABC report is thinly sourced. The gist is:
Sen. Hillary Clinton will hold an event with supporters by Friday, likely ending her historic bid for the White House and ceding the Democratic nomination to Barack Obama, ABC News has learned.
Late Update: The New York Times‘ Adam Nagourney is reporting the same thing, citing a senior adviser to Clinton:
Senator Hillary Rodham Clinton is moving to suspend her campaign and endorse Senator Barack Obama on Friday after Democratic members of Congress urged her Wednesday to leave the race and allow the party to coalesce around Mr. Obama, according to a senior adviser to Mrs. Clinton.
Mrs. Clinton is likely to make the announcement in New York City, an aide said, though no final venue has been chosen.
Her decision came after a day of telephone conversations with supporters on Capitol Hill about what she should do now that Mr. Obama had claimed enough delegates to be able to clinch the nomination. Mrs. Clinton had initially said she wanted to wait before making any decision, but her aides said that in conversations, some of her closest supporters said it was urgent that she step aside.
Later Update: CNN, too:
CNN can confirm through multiple sources as well as a top Clinton fundraiser that Sen. Hillary Clinton will drop out of the presidential race on Friday, ending her historic bid for the White House.