The announcement came in emails from John D. Podesta, Mrs. Clinton’s campaign chairman, to donors and others.
“I wanted to make sure you heard it first from me – it’s official: Hillary’s running for president,” the email reads. It goes on to say that Mrs. Clinton will soon meet with voters in Iowa and will host a formal kickoff event some time next month.
Mr. Podesta ends the email by referencing what is likely to be a major theme of Mrs. Clinton’s campaign. “We need to make the middle class mean something again,” it says.