The U.S. House of Representatives approved significant increases in funding for scientific research Wednesday, moving one step closer to reversing years of stagnant grant money long criticized by Harvard and other research centers.

The bill would add $3.5 billion for the National Institutes of Health, which serves as the most significant source of the University’s federal research funding by far. The legislation would also give an additional $3 billion to the National Science Foundation, another key financial backer.

The increases are part of a broader $819 billion economic stimulus package passed by the House. The Senate is set to consider a similar version of that legislation next week.

Harvard chief lobbyist Kevin Casey said it is likely that the bill will pass “in the near future.” Democrats are hoping to ready a final version of the bill for President Barack Obama’s approval by the second week of February.

Massachusetts, with its myriad research hospitals and universities, is the nation’s largest recipient of NIH funding per capita and is second only to California in overall funding. In 2007, Massachusetts received $2.2 billion in NIH funding—roughly 10 percent of NIH’s $22.8 billion spent on extramural research. Harvard received $1.4 billion, or 60 percent of the state’s allocation.

Casey said he believed the stimulus represented a “substantial infusion of funds” for scientific research, and added that the money would have a “very immediate impact on good jobs and excellent science.” NIH has seen flat funding since 2003, with purchasing power decreasing by 13 percent due to inflation.

As a result, the NIH now funds less than two of every ten grant applications, and thousands of approved projects await funding, according to Harvard statements on the issue.

NIH has said some of the money from the stimulus package could be awarded in only four to six weeks, according to Casey.

Harvard has used its clout to push hard for more federal science funding, and Casey said that its representatives have been on Capitol Hill, arguing directly to senators and house members that such a sweeping economic stimulus package would be incomplete without funding for basic research and “intellectual infrastructure.”

Earlier this month, the Massachusetts Life Science Collaborative—co-chaired by University President Drew G. Faust and the heads of MIT, Genzyme Corporation, and the University of Massachusetts—wrote a letter to the state congressional delegation advocating for increases in NIH funding, writing that each grant awarded creates an average of seven jobs, and that every dollar invested in the NIH generates twice as much in economic output.

They also wrote that “the next generation of scientific leaders [has been discouraged] from pursuing careers in biomedical research” as a consequence of eroding federal NIH support and delays in grant-making.

Glen Comiso, a director at the Life Sciences Collaborative, said that the House bill is fairly comprehensive and is “in the range” that Harvard and other institutions have been seeking for years. But he added that while the funding meets short-term needs and would help clear the clogged pipeline of NIH projects, the Collaborative wants to ensure that there would be adequate long-term funding as well.

The bill also allocates billions of dollars to increase the maximum award levels for Pell Grants and Stafford loans that go toward undergraduate financial aid. While Harvard’s comparatively generous aid program may dampen the need for such federal funding, Casey said that Harvard has tried to “raise [its] voice in the national interest and not simply in Harvard’s best interest.”

—Staff writer Peter F. Zhu can be reached at pzhu@fas.harvard.edu.