No one takes more thankless jobs within the Senate Democratic leadership than Patty Murray, and the Washington state Democrat may finally be in a position to reap the rewards.

During her almost six years as No. 4 in the leadership ranks, she’s been largely inconspicuous. But over time, her workhorse reputation has helped her amass considerable influence in the caucus. That is likely to continue as she takes the gavel of the Budget Committee in the 113th Congress.

“Whenever there’s something that’s hard to do, we go to Patty, and she delivers,” Majority Leader Harry Reid said on election night as it became clear his caucus would beat the odds and actually expand in the next Congress.

Reid also told elated Democrats, “There is no one who has ever done a better job of running the senatorial campaign committee than Patty Murray.”

No doubt that line caught the attention of Sen. Charles E. Schumer of New York, who served as chairman of the Democratic Senatorial Campaign Committee for two cycles, sweeping his party into the majority. Many view Schumer as a likely successor to Reid whenever he steps aside.

Another potential majority-leader-in-waiting, Majority Whip Richard J. Durbin of Illinois, called Murray the “she-ro” of the Senate Democratic Conference earlier this week and predicted she would “have an expanded responsibility with this new Senate.”

While Schumer and Durbin may see each other as their greatest rival, they may now need to start looking over their shoulders at Murray.

Reid has often looked to Murray to step into the breach when no one else would or could be trusted.

Murray talked to Roll Call this week about how her intimate knowledge of the caucus will aid her as she continues to shape the caucus’s policy objectives, especially when it comes to the fiscal cliff.

“I have an opportunity in leadership to really help focus where we are going to go in terms of policy: what issues are going to be on the table and how we frame them. From a political perspective, I know the players. I know what their states are like,” Murray said, stressing her campaign work. “I know what makes them tick and what they need in order to be successful, and the ability to work with all of them knowing that.”

One Senate Democratic leadership aide suggested Murray’s method of expanding her portfolio in some ways follows the pattern of Schumer’s move to become the top messaging strategist for Senate Democrats. Other sources agreed Murray will have the chance to gain more influence in the negotiations on the fiscal cliff and into next year if she asserts her prerogatives as Budget chairwoman.

After his own successful stint at the DSCC, Schumer took on the role of conference vice chairman and added responsibilities for communications strategy with the establishment of the Democratic Policy and Communications Center that brought together Reid’s leadership “war room” and the old Democratic Policy Committee.

Murray seems keenly aware that many underestimate her. During the interview, she was quick to return to the story that launched her career, when a local lawmaker dismissed her as a “mom in tennis shoes” who had no chance of becoming a senator.

In addition to chairing the Budget Committee, Murray will continue as conference secretary.

When the late Senate Appropriations Chairman Robert C. Byrd, D-W.Va., was too frail to manage spending bills on the floor, Murray did it despite being outranked on the panel by at least five other members. In the fall of 2010, at least three other senators turned down Reid’s request that they take on the seemingly impossible task of defending 23 Democratic seats from a GOP takeover in 2012. He finally persuaded Murray, and her fundraising and candidate recruitment led to the caucus adding two seats to its majority.

Six months after taking the DSCC job, Reid was back with another big ask: co-chairing the supercommittee on deficit reduction. The odds were stacked against her again, and the effort failed under the weight of the partisan divide between the House GOP and Senate Democrats.

Asked about her propensity for taking jobs few covet, Murray replied, “My mother forgot to tell me how to say no.”

While there’s still a formal process to go through, Murray has the seniority to take the Budget job being vacated by retiring Sen. Kent Conrad, D-N.D.

Murray said that in her many years of Senate service, she has seen Budget chairmen use a variety of methods to wield influence. Conrad, for example, has focused on the debt and deficit issues.

But Murray envisions a bigger role for herself.

“Jim Sasser really used his role as Budget chair with the leadership to write the economic policy for how we were going to move forward. I’ve seen Chairman Ryan in the House use it not to just write numbers on a paper but really define policies and how they’re going to fight for Medicare changes,” Murray said.

Sasser, a Tennessee Democrat, chaired the Budget Committee for two terms in the early 1990s. Rep. Paul D. Ryan, R-Wis., is expected to be Murray’s House counterpart next year, after running unsuccessfully as GOP presidential nominee Mitt Romney’s running mate.

Murray was candid in expressing her vision for the job.

“It is writing the budget; it is helping to define the budget to the country and to Congress and to moms at home in my state who are getting up and sending their kids off to school and saying, ‘What does it matter?’ Well, it matters if your child wants to go to college, if your husband needs job training to get a job or whether or not we are able to … ship the product that you are making overseas,” Murray said.

“If we just look at the budget as ‘how do we deal with this debt and deficit’, we are going to short-change the ability for this country to be who we’ve always been: a place of opportunity, in the global marketplace, competitive, forward-leaning and able to invest in our people in this country to be … at the top,” Murray said.

Meredith Shiner contributed to this report.