Sen. Barbara Mikulski (D-Md.) announced her endorsement of Sen. Hillary Rodham Clinton (D-N.Y.) on Tuesday, becoming the first non-home-state Senator to take sides in the 2008 Democratic presidential race. [IMGCAP(1)]

Clinton has been endorsed by Sen. Charles Schumer (D-N.Y.), while Sen. Barack Obama (D-Ill.), her main rival for the party’s White House nod, has the support of fellow Illinois Sen. Dick Durbin (D).

Mikulski will serve as a chairwoman of Clinton’s campaign.

“I have only the greatest respect for our field of Democratic candidates, but today I am proud to endorse Senator Clinton for President,” Mikulski said in a statement released by Clinton’s campaign. “As the first Democratic woman elected to the Senate in my own right, I am honored to join Senator Clinton in this historic effort to break the last barrier for women in public life.”

— Lauren W. Whittington