Sen. Barbara Mikulski will formally submit Hillary Clinton's name as the Democratic nominee for president at the party's convention.
Mikulski made the announcement Tuesday at a breakfast for Maryland delegates at the convention.
Rachel MacKnight, a Mikulski spokeswoman, says Mikulski will introduce Clinton's name at about 5 p.m. and give a brief speech before the roll call of the states.
Mikulski is the longest-serving woman in Congress and a long-time friend of Clinton. She is retiring at the end of her term, after serving five, six-year terms.
Maryland state Sen. Susan Lee, a delegate who was at the breakfast, says Mikulski has been a role model for women in politics.
Yvette Lewis, a Maryland superdelegate who was at the breakfast, says Mikulski is the perfect person to "pass the mantle."