It was implemented by former President Obama after the 2012 Sandy Hook shooting, which saw 20 students and six teachers killed at an elementary school by 20-year-old Adam Lanza.
But lawmakers, with the backing of the National Rifle Association and advocacy groups for the disabled, opposed the regulation and encouraged Congress to undertake a rarely successful process created to void regulations that Congress takes issue with.
The president is expected to sign it.
A controversial gun control regulation, finalized in the final weeks of the Obama administration, appears to be reaching the end of its very short lifespan.
The NRA, the ACLU and some advocates for individuals with disabilities say the rule deprived disabled Social Security beneficiaries of their Second Amendment rights without any court order or adjudication, and was indiscriminately broad.
Sen. Charles Grassley, R-Iowa, chairman of the Senate Judiciary Committee, said the regulation issued by the Obama administration was too vague.
Retails sales tick up in January, as consumer confidence grows
Economists polled by Reuters had forecast retail sales ticking up 0.1 percent and core sales gaining 0.3 percent last month. Sporting goods stores' sales increased 1.8%, and sales at health and personal care stores increased 0.7%.
"The Second Amendment, as a fundamental right, requires the government to carry the burden to show a person has unsafe mental illness", he said. The government was supposed to start enforcing the rule this December. It only would apply to those receiving disability benefits.
Sen. Chris Murphy, D-Conn., said he didn't know how he could explain to his constituents that Congress was making it easier rather than harder for people with serious mental illness to have a gun.
"If you can't manage your own financial affairs, how can we expect that you're going to be a responsible steward of a risky, lethal firearm", Murphy said.
The American Civil Liberties Union was also against the rule, also saying it stigmatized the mentally ill.
Democrats agreed the government must not stigmatize those with disabilities but said the rule affects a small group with severe, long-term mental disorders preventing them from doing any work. That was a loophole that the federal mandate to the Social Security Administration could have, ideally, partially closed.
"If there are problems with this rule, they can be addressed by fixing it", said Senate Minority Whip Richard J. Durbin, Illinois Democrat.