On Election Day, voters in Oregon, Alaska and Washington, D.C., voted to liberalize their marijuana laws, decriminalizing the possession or sale of the substance. But while Oregon and Alaska will be able to go ahead and start implementing their laws, D.C.’s more modest measure will first have to make it through a Republican Congress.

Once D.C.’s city council submits the measure to Congress, Congress will have 30 days to review it and during that time can pass a measure overriding it. Rep. Andy Harris of Maryland has vowed to use all of his political power to stop D.C.’s decriminalization measure from moving forward, including passing a spending bill rider barring the District from implementing its own law.

While D.C. will now be contending with Republicans controlling both chambers of Congress, it’s not clear how much support the GOP congressmen trying to stop the law will get from their colleagues. Republican Rep. Dana Rohrabacher of California, for instance, has said that overriding D.C.’s law would violate the GOP’s “fundamental principles,” including “limited government” and “states’ rights.”

But other conservatives have no such compunction. In an email to members of his organization on Friday, Family Research Council President Tony Perkins backed Harris’ effort to stop D.C. from implementing its decriminalization law by arguing that with a spending bill coming up, Harris “might finally have a way” to give the self-governed city with a population bigger than Vermont and Wyoming “the oversight it desperately needs” from congressional Republicans.