Sen. Barbara MikulskiBarbara Ann MikulskiTwo women could lead a powerful Senate spending panel for first time in history Harris invites every female senator to dinner next week Will the real Lee Hamiltons and Olympia Snowes please stand up? MORE this week will become the longest serving female senator in U.S. history. 

The feisty Maryland Democrat was first elected to the upper chamber in 1986, and was reelected to a sixth term last month. 

A champion of women's health issues and abortion rights, Mikulski will take the longevity crown on Wednesday when she's sworn in, surpassing Margaret Chase Smith (R), who represented Maine in the Senate from 1949 to 1973.


On Sunday, Senate Majority Leader Harry ReidHarry Mason ReidAfter the loss of three giants of conservation, Biden must pick up the mantle Photos of the Week: Voting rights, former Sen. Harry Reid and snowy owls Black Democrats hammer Manchin for backing filibuster on voting rights MORE (D-Nev.) issued a statement lauding Mikulski's service. 

“Barbara Mikulski has been a mentor and role model to countless members of this body, men and women on both sides of the aisle," Reid said. "In the spirit of Margaret Chase Smith, whose record she surpasses, Barbara has never stopped fighting for those who need an advocate."

If Mikulski remains in office through March of 2012, she'll become the longest-serving female member in the history of Congress.