Rep. Andy Harris (R-Md.) says he wants to use the federal appropriations process to bar the District from implementing its assisted-suicide law. (Andre Chung/For The Washington Post)

Republicans on Capitol Hill said Wednesday that Congress is unlikely to act in time to block the District’s assisted-suicide law before it takes effect Saturday, handing city officials an inadvertent victory against congressional intervention.

“Very doubtful it can get to the finish line,” said Rep. Jason Chaffetz (R-Utah), chairman of the House Oversight and Government Reform Committee, which voted Monday to strike down the D.C. law. “We’re just flat-out running out of time.”

But as the city prepares to implement the law, federal lawmakers are working on another line of attack: using the appropriations process to neutralize the law.

Rep. Andy Harris (R-Md.) said that he was confident the assisted-suicide law could be effectively stifled through the appropriations process and that he would “absolutely” pursue such an amendment.

Harris said there is still time to block the law because it is going to take District agencies several months to set up the required process before terminally ill residents can try to obtain life-ending drugs, and the city has to identify funds for that project.

“The D.C. government has to do some various things in the [law]: They have to develop a form. They have to receive a form. They have to process a form. They have to do studies,” he said.

Chaffetz has said that he is morally opposed to the District’s law — which will make it legal for doctors to prescribe lethal doses of medications to terminally ill patients — and that he thinks Congress should intervene, no matter what form that action takes.

Rep. Tom Graves (R-Ga.), chairman of the appropriations subcommittee that has jurisdiction over the District, declined through a spokesman to say whether he would support efforts to block the assisted-suicide law.

At D.C. government headquarters, Mayor Muriel E. Bowser (D) and council members all but declared victory over Chaffetz, even as they acknowledged that another fight with Congress over the funding of the measure appeared likely in coming months.

Although the law is set to take effect Saturday, terminally ill patients will not be able to seek lethal doses of medications for several months, possibly not until October. The mayor and council must first appropriate $125,000 to create a way for doctors to document requests for life-ending drugs and for the city’s medical examiner to create a classification for reporting deaths that ensue.

Unless the city takes urgent action, funding for the law would be included in the annual spending plan that takes effect Oct. 1. Terminally ill patients would then have to make two requests of a doctor for life-ending drugs over a period of two weeks. Doctors are also not required to abide by patients’ requests.

A spokesman for Bowser said it was possible that the mayor and council might move more quickly to implement the law before Congress can stop it.

“We are committed to ensuring this legislation becomes law and will keep all options on the table to implement it should Congress attempt to meddle in our local affairs,” spokesman Kevin Harris said.

Council member Mary M. Cheh (D-Ward 3), who wrote the legislation, said she was tentatively celebrating. “Yea, yea, yea. Of course I’m very happy the time period will expire before they can disapprove,” she said.

But Cheh said the episode raised questions about the District’s autonomy. Chaffetz “has shown the effort to try to frustrate other measures of ours, so it is going to make us a lot more insecure about the feeble democracy that we have being eroded further.”

Chaffetz has expressed concern about the city’s new fund to help undocumented immigrants fight deportation, Sen. Marco Rubio (R-Fla.) has said he wants to eliminate the District’s gun laws, and Harris wants to bar the city from spending money to regulate recreational marijuana use, which voters overwhelmingly approved in a 2014 ballot measure.

Eleanor Holmes Norton, the District’s nonvoting delegate to Congress, said she thinks the House did not move swiftly on Chaffetz’s plan because a floor vote would have put some members in an awkward spot. Two dozen House Republicans represent states that have assisted-suicide laws, including House Majority Leader Kevin McCarthy (R-Calif.), she noted.

But attaching language to an appropriations bill allows Chaffetz and other opponents of the assisted-suicide law to eliminate the measure without attracting the attention that a stand-alone vote would draw.

Rep. Mike Quigley (D-Ill.), the top Democrat on the appropriations subcommittee with jurisdiction over the District, said he would fight for the District’s right to enact its own laws.

“It is a little bit a back-door approach to accomplish the same things,” he said. “Here we are in appropriations trying to divvy up scarce resources, and our time is spent talking about states’ rights and federalism,” he said.

Meanwhile, on Wednesday, about 150 residents with DC Vote, which pushes for District statehood and autonomy, walked the halls of Congress to lobby for a “hands off” approach by Congress toward the city.

Bo Shuff, the group’s director of advocacy, said he expected Congress to target the “progressive agenda that D.C. believes in.” The group had 43 meetings with members of Congress and their staffs but was not granted an appointment with Chaffetz.

“If Jason Chaffetz is going to try to pretend to be our city councilman,” Shuff said, “he should probably come and meet face-to-face with us.”