Adam Eidinger, center, chairman of the DC Cannabis Campaign, and other protesters demand that Congress remove a provision that would overturn a ballot initiative legalizing marijuana. (Sarah L. Voisin/The Washington Post)

The congressional effort to block marijuana legalization in the District has been widely viewed as yet another frustrating defeat for self-governance by residents of the nation’s capital.

But city leaders are saying otherwise, promising to throw the issue back to Congress next month in a way that could prompt the most high-profile showdown in years over D.C. rights.

The giant federal budget bill that passed in the Senate on Saturday includes a provision, inserted by Republicans, that prohibits the city from spending tax dollars to enact the marijuana initiative.

D.C. Council Chairman Phil Mendelson (D) said Friday that he plans to ignore the provision and instead follow the usual procedure for a voter-approved referendum in a city required to submit to federal oversight: He will send a bill implementing Initiative 71 to Congress in January for a 30-day review, during which federal lawmakers can veto it or let it stand.

“I don’t feel that I have any choice,” Mendelson said. “The voters have spoken.”

The status of marijuana laws across the nation.

D.C. Democrats say they are ready to wager that Republicans will be unwilling to get bogged down in overturning the city’s marijuana law, which 7 in 10 voters supported in last month’s election. Doing so, Republican strategists acknowledge, risks exposing a divide between Republican conservatives and libertarians that could prove consequential to the 2016 presidential race.

Advocates are also hoping that Republicans, who will arrive back in Washington with a new Senate majority, will have their sights set on other matters, such as overturning President Obama’s actions on immigration and health-care reform.

Some congressional Republicans have indicated that they are ready to do battle on District turf — by trying to loosen the city’s strict gun-control measures and other liberal policies. However, Del. Eleanor Holmes Norton (D), the District’s nonvoting member of the House, said those issues will be up for debate regardless and the District doesn’t have anything to lose in provoking further confrontation over marijuana.

“Should we accept that it was already struck down, or should we make them work for it?” Holmes Norton said of the cohort of conservative House Republicans who successfully included the measure targeting the pot initiative in the $1.1 trillion spending bill.

“The question is, what should the District’s posture now be . . . and it’s absolutely continue the fight,” she said. “Adopt your own interpretation of what the [budget] language means and put the burden on them [the Republican majority] to strike it down. Do not acquiesce.”

Congress has the power to not only decide the District’s share of federal funds, but also to override how it appropriates more than $4 billion in locally raised tax revenue.

Over four decades of partial autonomy but no vote in Congress, the system has led to repeated battles between Capitol Hill overseers and the city. The District’s stance of protest has taken on a permanent quality, with an unofficial motto, “Taxation without representation,” printed on city license plates.

The fight for D.C. autonomy comes as the city is preparing to usher in a new mayor and new council members and when tens of thousands have streamed into the city. But the battle has waxed and waned since the 1970s.

“I’m having deja vu all over again,” said Wayne Turner, a health-care lawyer who led the fight with Congress that began in 1998 to let D.C. follow California with a voter initiative to legalize medical marijuana.

Two weeks before D.C. voters went to the polls that year, Congress passed a spending bill with a provision that preemptively suspended the medical marijuana initiative, leaving D.C. elections officials unwilling even to count the ballots for fear of congressional retribution.

The election eventually showed that city voters overwhelmingly backed medical marijuana, but congressional Republicans — and later, Democrats — carried over the prohibition in the federal budget for 10 years.

Turner said he fears that another protracted battle looms over legalization.

“I think this is a teachable moment, not only for people across the country about the District’s lack of rights, but also for the many newer residents who have moved into the city in the past several years,” said Turner, whose partner, Steve Michael, died of AIDS during the city’s 1998 petition drive for medical marijuana.

This time, D.C. leaders are preparing from the start to go on the offensive, and they are seizing on a technicality in the bill to push the issue to a showdown.

D.C. officials say the provision barring D.C. from moving forward on marijuana legalization was muddled just enough that they have an opening.

Unlike in other parts of the spending bill, there are some words missing. The part targeting D.C.’s marijuana initiative states that funding is barred only to “enact,” not to “enact or carry out” laws related to reducing drug penalties in the city.

Norton said she was told by Democratic budget negotiators that the omission was made on purpose to give city leaders a chance to argue that in moving forward, the District is only carrying out, and not enacting, the measure.

Still, the District may not spend any money to do so — or at least, not any money appropriated in the current budget year — if it is to comply with the letter of the budget bill. The District will have to maneuver carefully to do so. The initiative must be sent to Congress for a mandatory 30-day review. And the city must enact a law changing its drug penalties and publish those changes in the District register — all ministerial acts that will come with at least some staff time and cost.

In 1998, tabulating the results of the medical marijuana initiative cost, by one estimate, just $1.64, but the elections department refused to spend it.

Mendelson’s act of transmitting the marijuana initiative to Congress, therefore, could in itself amount to a violation of the federal spending bill if it could be shown to require any expenditure of city tax money.

District attorneys met repeatedly last week to debate whether the council and mayor could tap city reserve funds from prior years or solicit donations to pay for staff time and other incidental costs to move ahead.

District officials said that there is no line-item for transmitting bills and that they could not easily assign a dollar amount to the everyday task.

Notably, district attorneys — who have recently been quick to issue legal opinions on even more complicated matters — were silent for days last week on the legality of Mendelson transmitting the initiative to Congress.

On Friday evening, the office of the attorney general in the District issued a two-sentence statement saying only that it was continuing to review the federal budget legislation and will continue to assess how it may provide District policymakers “opportunities to implement the will of the people reflected in Initiative 71.”

One of those advocating for a workaround is Walter Smith, executive director of the D.C. Appleseed Center for Law and Justice. Smith said he had been in contact with the D.C. Council’s top attorney to urge the city to fund implementation of Initiative 71 much the way the it tapped its emergency reserves early in the year to stay open during the last federal government shutdown.

“There are ways,” Smith said. “I don’t think the council or Phil Mendelson really want to look like they are sticking the finger in the eye of Congress, but this isn’t that at all. It’s just saying that under the Home Rule Act, we have other options.”

Mendelson said he sees no choice but to push the issue back to Congress.

“This is just procedural,” he said, playing down any intent to provoke Congress.

Mendelson has told advocates of marijuana legalization that he believes the District can make the case that the law has already been enacted. In an interview with The Washington Post, he pointed to a letter he received Thursday certifying the results of the marijuana initiative that said he “must” transmit the legislation to Congress.

“The results indicate that the Initiative was ratified by a majority of voters. . . . You must transmit the measure to the Speaker of the House of Representatives and to the President of the Senate forthwith,” said the letter from elections board chief Cliff Tatum.

Rep. Andy Harris (R-Md.), who proposed the anti-marijuana measure that became part of the budget bill, warned that D.C. should tread carefully.

“The intent of Congress is clear — and has strong bipartisan support,” Harris said, noting that 57 Democrats joined Republicans in passing the spending bill in the House.

Michael Fauntroy, an associate professor of political science at Howard University who has authored a book on the District’s fight with Congress, said the showdown over marijuana policy may broaden awareness nationally of the District’s lack of voting rights, but it’s not the worst offense he’s witnessed.

“Nobody is surprised or should be surprised that this is happening. We tend to become prisoners of the moment, and the thing that happened most recently is what we get so exercised about,” he said. “But if you go back over history, there is a long list . . . Congress doesn’t hesitate to jump in when they have a point to make.”