By Ben Pershing
Washington Post Staff Writer
Wednesday, January 5, 2011; 12:16 AM

With a new Congress beginning, hundreds of new lawmakers will be sworn in Wednesday. But only one will break a record that's lasted four decades.

At the moment Sen. Barbara A. Mikulski (D-Md.) completes the oath to begin her fifth term in the chamber, she will become the longest-serving female senator, surpassing the 24-year tenure of Sen. Margaret Chase Smith (R-Maine).

When she took office in 1987, Mikulski recalled in a recent interview, "women were so rare even holding statewide political office. . . . I was greeted with a lot of skepticism from my male colleagues. Was I going to go the celebrity route or the Senate route? I had to work very hard."

No one is skeptical anymore.

The Senate will take up a resolution commending her achievement Wednesday, with a bipartisan cast of lawmakers paying tribute. About 25 friends and family members will be there to watch - Mikulski had to bum extra tickets from colleagues to fit them all in. She'll get a reception in her honor in the historic Russell Caucus Room and then attend a private party with her former top aides.

Among Mikulski's many firsts is that she was the first female Democrat to serve in both chambers of Congress and the first female Democrat to be elected to the Senate without succeeding her husband or father. In the Senate, she was the first woman to chair an appropriations subcommittee and the first woman to serve on a handful of other panels.

And now, she'll be the first woman to serve a quarter-century in the Senate.

There are two ways to look at the milestone: as a symbol of just how far Mikulski, 74, and her fellow female senators have come, or of how much further they have to go.

Mikulski's tenure puts her first all-time among women, yet dozens of men have served longer - including 13 current senators.

When Mikulski took office in 1987, she was one of two women in the Senate. That number rose to three in 1991 and then to seven after the 1992 election, known as "the Year of the Woman." The total has continued to climb, although not quickly.

Of the 13 new senators elected in November, just one - Kelly Ayotte (R-N.H.) - is a woman. And because Sen. Blanche Lincoln (D-Ark.) lost her reelection race, the overall number of women serving in the Senate will stay at 17 for the second consecutive Congress.

"I would have a more 'glass is half empty' outlook on this one," said Jennifer Lawless, director of the Women & Politics Institute at American University. "When we are 52 percent of the population and only 17 percent of the Senate, it's difficult to say we've made so much progress, especially when that number has plateaued."

Lawless said women are less likely than men to be recruited to run for statewide office, and her research has shown that women are also less likely to think they're qualified to run for office.

That's why Mikulski urges female candidates to take some risks.

When Sen. Barbara Boxer (D-Calif.) was considering giving up a safe House seat to run for the Senate in 1992 - just as Mikulski did in 1986 - she went to Mikulski for guidance. Mikulski's advice, according to Boxer, was: "You must be sure you're willing to leave the House and you're willing to lose."

Although some of her colleagues describe Mikulski as a leader of the Senate's female members, Mikulski said she doesn't see herself that way.

"I see myself as the convener," she said. "Every woman in the Senate is already a leader."

Sen. Dianne Feinstein (D-Calif.) used another label to describe Mikulski.

"She is really sort of the dean of the women," Feinstein said.

Feinstein recalled that Mikulski reached out when she was first running for Senate in 1992 to provide encouragement and that she gave more advice after Feinstein was elected. Other colleagues - including Republicans - said they'd had the same experience.

"Barbara takes all of the new women senators under her wing," said Sen. Susan Collins (R-Maine). "I remember when I was sworn in in 1997, she was one of the first people to call me to congratulate me and offer to help me, particularly by teaching me about the appropriations process."

About every other month, the Senate women get together for dinner. The gatherings were Mikulski's idea, and she also came up with the distinctly un-Washingtonian ground rules that have made them successful: no staff, no memos and no leaks.

Mikulski said the purpose of the meals is "friendship and fellowship," relatively scarce commodities in the modern Senate.

Several female senators said they feel better able to work together across party lines than their male counterparts are, and they attribute that partly to encouragement from Mikulski.

"Maybe it's because she's a social worker, maybe because she's a woman - she understands relationships are everything," said Sen. Patty Murray (D-Wash.). "She helps you see areas of common interest so you can find solutions."

For all the praise of Mikulski, Sen. Mary Landrieu (D-La.) noted that "she's not a saint. She can be tough and gruff." But, she added, in politics, "some women . . . are so intent on getting wherever they're going fast or first, and Barbara's not like that. She's the opposite."

When Mikulski came to the Senate, the one woman in the chamber at the time - Sen. Nancy Kassebaum (R-Kan.), who later became Nancy Kassebaum Baker - told Mikulski that while women weren't allowed in the Senate gym, they were allowed in the committee rooms. So that was where Mikulski decided to make her mark - as a legislator.

Despite the attention she could accrue as one of just two women in the chamber, Mikulski said, "I wanted to be known more for my amendments than for photo-ops in People magazine."

Mikulski has been an advocate for women's health, the space program and steering money to Maryland via her perch on the Appropriations Committee. Her proudest moments in office, she said, include writing the Spousal Anti-Impoverishment Act - which helps to keep seniors from going bankrupt while coping with the costs of spouses' nursing home care - and fighting to save the Hubble Space Telescope.

Mikulski was born and raised in Baltimore and was a social worker before entering politics as a member of the Baltimore City Council in 1971. She first ran for the Senate in 1974 and lost, then won a House seat in 1976. She was elected to the Senate a decade later and has won reelection with relative ease ever since; she captured a fifth term in November with 62 percent of the vote.

She is known on the Hill for being brash and outspoken, an outsize presence in any room despite her short stature. Mikulski is also fond of making self-deprecating jokes about her height and her hair. She recognizes the importance of humor, said Sen. Claire McCaskill (D-Mo.).

"She's funny - that is an incredibly important skill set if you're in a business like politics," McCaskill said. "She has had a unique ability to stay grounded, and she's done a lot of that with humor."

So after Wednesday, what's next on Mikulski's list of goals? In March 2012, she would become the longest-serving woman in Congress, surpassing the 35-year tenure of Rep. Edith Nourse Rogers (R-Mass.).

Mikulski said she isn't thinking about setting any records beyond Wednesday's, and she joked that she's more concerned with working off whatever pounds she might have gained over the holidays.

"My next milestone," Mikulski said, "is getting back on the treadmill."

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