Diane Feinstein

Mikulski was influential in this barrier-breaking VP pickWhile it is a faint memory now, there was speculation up until the early summer of 1984 that then-Rep. Barbara Mikulski would make a good running mate for the Democratic presidential nominee.

She was one of three women House members considered for the job, the others being Pat Schroeder of Colorado and the female frontrunner, Geraldine Ferraro of New York. Outside Congress, two minor office-holders who would go on to national prominence -- San Francisco Mayor Diane Feinstein and Texas State Treasurer Ann Richards -- were also considered.

Female Dean of the Senate: Mikulski and other women Senators in the 110th Congress.Barbara Mikulski is the modern dean of women U.S. Senators. She gained that respect by climbing the ladder of Baltimore politics, spending a decade in the House, and another two decades in the Senate. Regardless of party, every one of her newly-elected female colleagues pays a visit to seek advice from a woman who has weathered the Senate for over two decades.

Mikulski is the longest-serving woman currently in the Senate, besting Senators Barbara Boxer, Diane Feinstein and Patty Murrary by about five years. At the end of her current term, Mikulski will surpass the longest-serving woman Senator in history, Maine's Margaret Chase Smith, who served four full terms.