UPPER MARLBORO, Md. (AP) — Maryland Rep. Chris Van Hollen’s campaign says Prince George’s County Executive Rushern Baker will endorse Hollen for U.S. Senate.

Baker is expected to announce his endorsement Wednesday at a news conference Wednesday in Colmar Manor.

Van Hollen, a Democrat, is running for the Senate seat currently held by Barbara Mikulski, who will retire. He has raised more than $1 million for his campaign.