WASHINGTON -- Rep. Roscoe Bartlett, R-Md., a noted budget hawk, has introduced a novel way to take a tiny chunk out of the federal deficit: Pinch pennies by preserving primates.

Bartlett joined with the Humane Society of the United States and the Physicians Committee for Responsible Medicine to stump for a bill to prohibit "invasive research" on chimpanzees and retire the approximately 500 government-owned chimps currently in laboratories to private sanctuaries within three years.

At a news conference Wednesday at the U.S. Capitol Visitor Center, Bartlett, who has a doctorate in human physiology, said science has changed and it is time to end chimp research.

"There's just no valid argument to continue to keep these great apes as they're now being kept," Bartlett said. "Very few of them are used in research and I'm not sure that any of them need to be used."

With his background in science and his reputation as a fiscal conservative, Bartlett would seem to be the perfect spokesman for the bill, called the "Great Ape Protection and Cost Savings Act."

With Bartlett's backing, it has become an endangered species of Capitol Hill politics: a bipartisan effort. The bill had almost 170 co-sponsors when it was introduced in the last congressional session, and already has 40 this time around -- a list that includes Democrats, Republicans and Independent Vermont Sen. Bernie Sanders.

Michael Markarian, the Humane Society's executive vice president of external affairs, said that 80 to 90 percent of the chimps in U.S. laboratories are not part of active research, but are being warehoused in crowded conditions at taxpayer expense. Under National Research Council guidelines published in 1997, "surplus" chimps may not be euthanized, but must be kept for their natural life span, which can run to 60 years.

Markarian's organization estimates that the bill could save $25 million to $30 million per year.

That figure is contingent on a lot of variables, though. According to Humane Society estimates, only about $7 million in savings would come from transferring the 511 government-owned chimps to private sanctuaries and ending government support of research on 244 privately-owned chimps. The rest of the savings -- about $22.2 million -- comes from ending the research itself.

The cost to medical advancements is also matter of debate. The Federation of American Societies for Experimental Biology opposed the bill when it was introduced last year, saying it would "harm medical research that helps both humans and great apes." The group noted that chimps are used as research models for a host of diseases, including hepatitis C, malaria and rotovirus.

"Our position on research using great apes has not changed," FASEB spokesman Howard Garrison said by phone Wednesday.

According to the New England's Anti-Vivisection Society's "Project R&R: Release and Restitution for Chimpanzees at U.S. Laboratories," the National Institutes of Health owns about 500 chimps.

NIH spokeswoman Jenny Haliski declined to comment on the pending legislation, but provided a link to an NIH website on animal research. It notes that the use of animals in research is heavily regulated, advanced computer research models often stem from animal research and that the polio vaccine was developed using a monkey as the research model.

But Elizabeth Kucinich, spokeswoman for PCRM and wife of Bartlett's ideological opposite, Dennis Kucinich, D-Ohio, said little would be lost in the world of medical research if the chimps were retired. She said there were significant physiological differences between chimps and humans -- particularly in their response to hepatitis C -- and the suffering and stress that chimps endure in captivity skews research results anyway.

Bartlett agreed, and said modern research methods with human cells are more effective than "whole animal" research. He said his own work with primates for NASA in the 1950s was necessary because methods were crude and human lives were at risk.

"Nobody had ever been weightless before and we had no idea what would happen when you were weightless," Bartlett said. "So this was a pioneering thing and it was probably a legitimate use of these animals."

He said better alternatives have been developed since then and groups like MD Anderson Cancer Center should no longer need primate research.

"I'm surprised that we're still doing whole-body experiments with cancer," Bartlett said. "I would think that they know enough about it now that they should be down at the cellular level."

MD Anderson spokesman Scott Merville said his organization is doing research at the molecular level, but also has 176 NIH-owned chimps, some of which are being used to test drugs targeting genes and proteins only present in humans and chimpanzees.