Sen. Patty Murray’s political career began on a dare.

Insulted when a Washington state lawmaker told her she “couldn't make a difference” while pushing for a preschool program targeted by budget cuts, she responded by organizing a coalition of 13,000 parents who fought successfully to save the program.

Now, the self-professed “mom in tennis shoes” is part of Senate Majority Leader Harry Reid's inner leadership circle, with Reid giving her increasingly more responsibility since she arrived in Congress in 1993.

As chairwoman of the powerful Senate Budget Committee, the Washington state Democrat reached a long-term budget deal with her counterpart on the House budget panel, Rep. Paul Ryan, R-Wis. The two-year, $2 trillion compromise, while only modestly addressing the nation's debt and spending issues, marked a truce in the partisan battles that have paralyzed Congress.

The stakes in the Murray-Ryan talks couldn't have been higher. Failure to reach agreement risked a second partial government shutdown in less than four months, with the prospect of public opprobrium raining down on both parties.

People who know Murray say no one was better suited for the challenge.

“She’s a long way away from the ‘mom in tennis shoes’ and now is a force to be reckoned with in the Senate,” said Jim Manley, a former Democratic Senate leadership aide who works with QGA Public Affairs in Washington. “She can go toe-to-toe with any of these guys” in the Senate.

Murray, 63, was raised in Bothell, Wash., outside Seattle. Her father, a World War II veteran and Purple Heart recipient, ran a five-and-dime store on Main Street, where she and her six siblings worked. She met her husband, Rob, while attending Washington State University. After graduating in 1972 with a physical education degree, she returned to her home area to teach preschool and later a parenting class at a community college.

Inspired by her first political success as a citizen lobbyist, Murray successfully ran for her local school board in the mid-1980s while raising two children, then was elected to the Washington Senate in 1988. Four years later, after incumbent U.S. Sen. Brock Adams retired while mired in a sex scandal, she jumped into the race as a heavy underdog.

Murray routinely campaigned as the “mom in tennis shoes” and portrayed herself as a voice for families. But the slogan led some to dismiss her as a political lightweight.

Chris Vance, a former chairman of the state Republican Party who served in the Washington Legislature with Murray, said he laughed when he heard she was running for Congress.

“It just seemed absurd,” Vance said.

But she easily beat former U.S. GOP Rep. Rod Chandler in the general election — showing Vance and others it was a mistake to consider her anything but a hardworking, shrewd political player.

“Is she a world-class intellect like [former Sen. Daniel Patrick Moynihan] or some kind of senator like that? Probably not,” said Vance, who works as a public affairs consultant in Washington state. “But it doesn’t matter [because] she’s been underestimated her entire career, and Republicans out here have never figured out what to do with her.

“For a lot of Republicans, there’s a notion that a senator should be this grand, imposing figure, not a mom in tennis shoes who’s barely 5 feet tall. ... But she’s an incredibly skilled lawmaker.”

Murray has been willing take on tough, thankless tasks that other Democrats have shunned. When party leaders needed someone to oversee the Senate's fundraising arm, Murray said “yes” twice, for both the 2002 and 2012 election cycles. In 2011, Reid asked her to serve as the Democratic chairman of the so-called “supercommittee,” a bipartisan panel that eventually failed to reach a debt-cutting deal, which triggered this year's automatic spending cuts.

“Those were two tough assignments with very little chance of glory,” Manley said.

But her loyalty hasn’t gone unnoticed by Reid, who recently bragged to a Las Vegas TV station that Murray is “one of my favorite people.”

That admiration has extended to Washington state voters, who have re-elected her with comfortable margins three times.

Luis Fraga, a University of Washington political science professor who has closely followed Murray's career, said that while Murray has championed many liberal positions -- from women's rights to immigration reform -- she is first and foremost a pragmatic politician who staunchly defends her state's main employers, including the military, agribusiness and aircraft manufacturer Boeing.

“She is very clear in stating what the grounds are for her positions,” Fraga said. “Not everybody agrees with them, but you know where she stands and you know why, and I think that helps her gain a reputation for being straightforward and transparent.”

Vance said Murray so far has an easy path toward re-election in 2016, caused partly by dysfunction in the state GOP.

“What Republicans need to say is, ‘Patty Murray is an incredibly powerful senator and has become part of the problem [in Washington]’, but they’ve always tried to imply that she doesn’t deserve to be there, and that’s exactly the wrong thing to do,” he said.

“Unless something dramatically changes, she’s not going to lose.”