As the science-literate fret about the impact on research of a new president taking office next January, changes in Congress, and in the Senate in particular, could have a major effect as well. Five U.S. senators are retiring whose departures could affect scientific policies and funding in a very significant way. We talked to experts from science-focused nonprofit organizations to ask about what makes a senator science-savvy, and what the departing politicians have done for science.

The first takeaway: Political champions of science are few and far between. "I think there's probably one person in five years who really understands how science works, why science is more than just another interest group,” says Rush Holt, CEO of the American Association for the Advancement of Science. (Holt, who has a doctorate in physics, also represented New Jersey’s 12th Congressional District as a Democrat for 16 years in the U.S. House of Representatives.) Because members of Congress seldom have scientific backgrounds, Holt says the number one predictor of interest in science is geography.

That’s because senators are more likely to care about science if they have a research center in their state, according to Michael Lubell, director of public affairs for the American Physical Society. Individual state interests, he adds, often make senators champions of particular areas of science—healthcare or energy, for example—rather than of science writ large.

Even within a specific area of science, like healthcare, politicians may focus more narrowly still. Senators commonly engage in disease-specific advocacy, says Nora Connors, the deputy director of public policy of the Public Health Institute, who previously advised Senator Dianne Feinstein (D-CA). Though targeting specific diseases is important, Connors says politicians need to think about health more holistically and address socioeconomic risk factors as well as diseases themselves

Retiring senators can have a particularly large impact on scientific policies and funding because even if their successors care just as much about the same issues, they’ll have to climb the seniority ranks before they can head senatorial committees and wield the accompanying influence.

So what do science advocates want from senators? Among other issues, climate change is top of mind for Holt, Lubell and Connors. Here’s how this year’s retiring senators scored on climate change and other issues:

Barbara Boxer (D-CA): Connors praises Boxer for supporting funding for Planned Parenthood and research on teen pregnancy. And as the ranking member for the Environment and Public Works Committee, Boxer paid special attention to climate change.

“Keeping fossil fuels in the ground has become the test of climate leadership in recent years,” says Jason Kowalski, the U.S. policy director for, a climate change-focused nonprofit. Boxer vocally opposed the Keystone XL pipeline—proposed to carry oil between Canada and the US—before presidential candidate Hillary Clinton and President Obama did. Boxer spent hours, talking with colleagues in Congress about the pipeline. “I would not use the word ‘negotiating,’” says Kowalski. “I would say ‘fighting them and winning.’”

Dan Coats (R-IN): Most of the science advocates we consulted knew little about Coats, who has released statements supporting the Keystone XL pipeline and criticizing the Environmental Protection Agency’s Clean Power Plan for “heavy-handed regulation on coal-fired power plants.” Matt McKnight, Congressional Champions Project director for the League of Conservation Voters says Coats ranks “pretty low” on environmental issues.

Barbara Mikulski (D-MD): As the vice chair of the Appropriations Committee, Mikulski has advocated for science funding, says Holt, likely in part because her state hosts the National Institutes of Health, NASA’s Goddard Spaceflight Center and the Hubble Space Telescope Science Institute.

“It’s a huge loss to science and healthcare,” says Connors of Mikulski’s retirement. “She’s been a longtime ardent supporter of healthcare and healthcare funding.”

Harry Reid (D-NV): As former Senate Majority leader, Reid “really did the behind-the-scenes wheeling and dealing” to get the Affordable Health Care Act passed, according to Connors.  

McKnight praises Reid for co-hosting national clean energy summits, which have furthered research in the area. “Senator Reid has been one of our strongest champions,” he says, “because he’s passionate about it, but he also has such an understanding of how to get things done in the Senate.” McKnight credits the summit for leading to Tesla’s new lithium ion battery factory outside Reno.

David Vitter (R-LA): Kowalski, McKnight and Connors criticize Vitter for doubting the existence of climate change. Vitter also supported the Keystone XL pipeline. Connors notes, however, that Vitter has been relatively supportive of NIH funding.

Lest it seem that science advocacy always follow party lines, Holt mentions outgoing Republicans in the House of Representatives who have taken strong stances on scientific issues: New York Republicans Chris Gibson and Richard Hanna both sponsored a resolution that recognized climate change and called to reduce further risks.

What’s more, none of the outgoing senators should be viewed as perfect, according to Holt, even those who took relatively strong positions on scientific issues.

"I can't think of anybody in the last 30 years who’s understood how badly we're underinvesting in science,” Holt says. “We should be talking about doubling or tripling federal support. We’re nowhere near diminishing marginal returns.”