Andrew Burton / Getty Images Senators Murkowski, Ayotte, center, and Collins, right, broke the logjam to open the government and avert default.

This article appears in the October 28, 2013 issue of TIME under the title “The Last Politicians.” To subscribe to TIME magazine for $2.99 a month, please click here.

At one of the darkest moments of the government shutdown, with markets dipping and both ends of Pennsylvania Avenue hurling icy recriminations, Maine Republican Susan Collins went to the Senate floor to do two things that none of her colleagues had yet attempted. She refrained from partisan blame and proposed a plan to end the crisis. “I ask my Democratic and Republican colleagues to come together,” Collins said on Oct. 8. “We can do it. We can legislate responsibly and in good faith.”

Senate Appropriations Committee chair Barbara Mikulski, a Maryland Democrat, happened to be standing nearby, and she soon picked up a microphone and joined in. “Let’s get to it. Let’s get the job done,” she said. “I am willing to negotiate. I am willing to compromise.” Ten minutes later, a third Senator stood to speak. “I am pleased to stand with my friend from Maine, Senator Collins, as she has described a plan which I think is pretty reasonable,” said Alaska Republican Lisa Murkowski. “I think it is pretty sensible.”

As with most anything that happens on C-SPAN, the burst of bipartisan vibes was meant to send a message. But behind the scenes, the wheels really were turning. Most of the Senate’s 20 women had gathered the previous night for pizza, salad and wine in the offices of New Hampshire Senator Jeanne Shaheen, a Democrat. All the buzz that night was about Collins’ plan to reopen the government with some basic compromises. Senator Amy Klobuchar, a Minnesota Democrat, proposed adding the repeal of the unpopular medical-­device tax. Senate Agriculture Committee chair Debbie Stabenow suggested pulling revenue from her stalled farm bill. In policy terms, it was a potluck dinner.

In the hours that followed, those discussions attracted more Senators, including some men, and yielded a plan that would lead to genuine talks between Senate leaders Harry Reid and Mitch ­McConnell to end the shutdown. The ­pieces were all there: extending the debt ceiling and reopening the government with minor adjustments to the ­implementation of Obamacare. No one doubted the origin. “The women are an incredibly positive force because we like each other,” Klobuchar boasted to TIME as the negotiations continued. “We work together well, and we look for common ground.”

It’s quite an irony that the U.S. Senate was once known for having the worst vestiges of a private men’s club: unspoken rules, hidden alliances, off-hours socializing and an ethic based at least as much on personal relationships as merit to get things done. That Senate — a fraternal paradise that worked despite all its obvious shortcomings — is long gone. And now the only place the old boys’ network seems to function anymore is among the four Republicans and 16 Democrats who happen to be women.

Cigars and poker are out. The women’s club offers some of the same benefits that came in the original men’s version, as well as some updates: mentor lunches and regular dinners, started decades ago by Mikulski, the longest-serving woman in the Senate, but also bridal and baby showers and playdates for children and grandchildren. An unspoken rule among what Collins calls “the sisterhood” holds that the women refrain from publicly criticizing one another. And there is a deep sense that more unites them personally than divides them politically. “One of the things we do a bit better is listen,” says North Dakota Democrat ­Heidi Heitkamp. “It is about getting people in a room with different life experiences who will look at things a little differently because they’re moms, because they’re daughters who’ve been taking care of senior moms, because they have a different life experience than a lot of senior guys in the room.”

The notion that women in power function differently from men, more ­collaboratively and thus more effectively, has long been an intuitively appealing but empirically unproven theory. Lately, the U.S. Senate has been running a lab test. Women now chair or sit as ranking members of 10 of the Senate’s 20 committees and are responsible for passing the vast majority of legislation this year, whether it be the budget, the transportation bill, the farm bill, the Water Resources Development Act or the Violence Against Women Act. They have driven the debate on everything from derivatives reform to sexual assault in the military.

Perhaps most important, they are showing how to make things happen. “I am very proud that these women are stepping forward,” says Senator John McCain, the Arizona Republican. “Imagine what they could do if there were 50 of them.”

(MORE: 11 Things You Don’t Know About the Senate Sisterhood)

Civility Above All

Whatever anyone says, official Washington remains a hidebound city. At the White House and on K Street, women still struggle for the top jobs, and in the House, the sole chairwoman, Candice Miller, leads a committee that oversees the Capitol’s in-house staff, cleaning and maintenance, shops and gardens. Inappropriate behavior, casual chauvinism and old-fashioned views of gender roles still pervade everyday life. A Senator waiting to get on an elevator once barked at Klobuchar that it was for Senators only. Her aide informed the man that she was a Senator. As the doors slid closed on his stunned face, Klobuchar quipped with a smile, “And who are you?” Almost all the Senate women have stories of being kept out of rooms, clubs, caucuses and huddles, of being patronized, hit on and scolded for abandoning their children. “Running for Senate, I did get a number of people who would ask, ‘What’s going to happen to your children?’” Kelly Ayotte, Republican Senator from New Hampshire, says. “My husband would be offended by that too.”

Against that backdrop, the private gatherings among the sisterhood are a source of both power and perspective. They occur every few weeks or months, depending on the need. Venues include the Senators’ homes — and occasionally the unlikely confines of the Capitol’s Strom Thurmond Room, a space named for one of the chamber’s most notorious womanizers. “We started the dinners 20 years ago on the idea that there has to be a zone of civility,” says Mikulski. Once a year the group also dines with the female Supreme Court Justices. Dianne Feinstein, who chairs the Select Committee on Intelligence, holds regular dinners for women in the national-­security world. Even the female chiefs of staff and communications directors have started regular get-togethers of their own. In April the Senate women breached their no-outsider rule by agreeing to dine at the White House with President Obama. Going around the table, California Senator Barbara Boxer remarked that 100 years ago they’d have been meeting outside the White House gates to demand the right to vote. (“A hundred years ago, I’d have been serving you,” Obama replied.)

It’s a diverse group, ranging in age from Feinstein, who is 80, to Ayotte, who is 45. Feinstein makes herself available to every new female Senator who wants advice on how she runs her offices. In her trademark pearls, she is Pacific Heights proper and even has a dress code for her staff: stockings and skirts of a certain length. Meanwhile, Ayotte and New York Senator Kirsten Gillibrand, a Democrat, get down and dirty during softball practice for a charity team they both play on and have been spotted in their offices in sneakers, still covered in mud.

Close political alliances have developed among several of the women. Boxer has taken a special interest in Massachusetts’ Elizabeth Warren — both are liberal firebrands. Democrat Claire McCaskill, who hails from a red state and faced a tough re-election campaign last year, made a point of courting Republican friendships early on. Sometimes those friendships trump party: Ayotte refused to campaign for fellow Republican Todd Akin, McCaskill’s opponent in 2012, and pointedly condemned him when he started sharing his theories about how women’s biology offers a natural defense against pregnancy from “legitimate” rape.

In private and public, strict rules of civility are enforced. At one recent dinner, Warren brought up antiabortion bills pending in the House, railing against Republicans for their “war against women.” Her complaint was greeted with admonitions from her fellow Democrats: We don’t talk about partisan issues here. Two of the 20 women are pro-life: Ayotte and Nebraska Republican Deb Fischer.

(MORE: Obama Signs Bill to End Government Shutdown, Avoid Default)

A Greater Responsibility

When Heitkamp voted against tightening gun laws after the Newtown school shooting, she was unprepared for the backlash, particularly from women’s groups. “A female friend in the Senate said to me, ‘You know, it’s because they feel you represent all women, not just the women of North Dakota,’” Heitkamp says. “And it just clicked for me for the first time. I was, like, ‘Oh, now I get it.’”

Most of the Senators say they feel they speak not just for the voters in their states but for women across America. Over the years they have pushed through legislation that has vastly expanded funding of women’s- and children’s-health research, testing and treatment. They’ve passed the Lilly ­Ledbetter Fair Pay Act and other anti­discrimination laws. And they’ve won federally mandated maternity and family medical leave. While most of these efforts were driven by Democrats, the women are strongest when they unite on legislation like the Homemakers IRA, which allows tax-deductible contributions to retirement plans by stay-at-home parents.

In April 2011, at the end of the budget debate, Patty Murray, a Democratic Senator from Washington, got a call at home from majority leader Reid summoning her to the Capitol. It was 11 p.m., and she found a room full of men who’d been working to avert a government shutdown. They said they were close to a deal, but cuts to Planned Parenthood sought by House Republicans were still on the table. Murray, who is the highest-ranking female Senator in leadership, hit the roof. “Absolutely not,” she recalls telling them. She organized four press conferences with female members over the next three days to highlight the importance of Planned Parenthood for providing not just abortions but also contraception, mammograms and children’s health. The funding was preserved.

That doesn’t mean the women always win. During the immigration-bill markup, Hawaii’s Mazie Hirono grilled South Carolina ­Republican Lindsey Graham about college-diploma requirements for new visas. She noted the disparity in female access to education in the developing world. “Could you share with us how you think that unmarried women would fare under the merit system?” asked ­Hirono, who immigrated with her mother to the U.S. as a child. Graham replied that they could come with their families. Hirono, Murkowski and 10 other women introduced an amendment to allot visas to health workers, nannies and those in other traditionally female professions. Though the measure was popular, it failed to get a vote in the Senate.

What Hasn’t Changed

Most of the legislation passed by female chairs this year has been gender blind: Stabenow’s farm bill, Boxer’s transportation and water-resources bill, Murray’s budget and Mikulski’s appropriations bills. All four of those chairwomen say their success comes from a willingness to deal and a disinclination to grandstand. Stabenow divvied up the farm bill like “a big sister handing out chores,” says Vermont Senator Patrick Leahy, a Democrat on the Agriculture Committee. And she was tough: Leahy said he was glad when the bill passed, if only to stop Stabenow “from calling me in the middle of the night.” Mikulski is effective, says Reid, because “everyone’s afraid of her.”

Some elements of Senate life, meanwhile, remain unchanged. Women still have a long way to go to match the clout of their male colleagues. Twenty-five states have yet to elect a woman to the Senate. Many committees have yet to see female chairs. A recent Institute for Women’s Policy Research study showed that at the current rate, it would take more than a century for women to reach parity in Congress.

Collins and her co-conspirators get the lion’s share of the credit for starting the process to break the weeks-long stalemate over government spending and the debt ceiling. “We need to be pragmatic. This is not going to be a Republican solution or a Democratic solution. This is going to be a solution that is good for the country,” Murkowski told NBC’s Today show on Oct. 16. “The six women that have been working together do have a good bipartisan solution.” But even the fate of their bid to end the shutdown was illustrative of how far women have to go in the Senate. Shortly after proposing a basic outline and convening a working group of 12 Senators — half of them women — ­Collins and her crew found the negotiations co-opted by the two party leaders, both male. Though much of the Collins plan became a part of the final talks, particularly the timelines and some small changes to Obamacare, the women no longer had control of the process.

That will likely have to wait a few more years, until a woman takes her place as majority or minority leader.

INTERACTIVE MAP: These Are the Republicans Who Voted for Government Default

