On Aug. 29, 2013, Deputy Attorney General James M. Cole published a memorandum to specify federal officials’ role in enforcing the ban on medical marijuana in the 21 states where it is legal. The paper drew a distinction between the “seriously ill and their caregivers” and “for-profit commercial enterprises,” stressing that the latter is a more “appropriate target” for the Drug Enforcement Administration.

Five months later, the owner of a Southern California legal medical marijuana dispensary, which serves 17,000 people who suffer from ailments like cancer, AIDS, and multiple sclerosis, was sentenced to a decade in federal prison. Three weeks later, in a similar case, a 70-year-old Washington state man and four family members were charged with six felonies each for operating a medical-marijuana collective in their community. If convicted, each face 10 years in prison.

The missive, while well-intentioned, didn’t work. Telling the Justice Department and DEA to stop undermining state medical-marijuana laws is one thing. Forcing them to abide by that directive through law is quite another.

Tonight, 12 congressman will present an amendment that could do just that: End the DEA’s brutal crackdown on medical marijuana. Is Congress ready to go ganja?

If Rep. John C. Fleming has anything to do with it, the answer will be a defiant “no.” The Louisiana Republican, who will be speaking tonight on the floor, is one of the few congressmen who continues to openly oppose medical-marijuana laws. In a hearing on doctors recommending medical marijuana to veterans in order to treat post-traumatic stress disorder this month, Fleming defended the Department of Veterans Affairs’ rules against it: “The last thing we should be doing is giving marijuana to people with these disorders.” The congressman pointed to a recent study by the American Heart Association that found a link between heart-related complications and marijuana in youths as one of the reasons for this stance. His office could not be reached for comment.

Others, such as Bill Piper, director of national affairs for the Drug Policy Alliance, disagree. “The general sense is that there’s a lot of momentum around this medical-marijuana bill, in part because of all the states—especially including conservative ones—that are now in play.” Piper said many members of Congress are frustrated with the DEA’s obstruction of the administration’s drug reform—an issue he attributes to DEA Director Michele Leonhart. “She’s living in a different world; she’s stuck in the 1980s,” he said. “I think she’s the last true believer in the war on drugs.”

Aaron Houston, political adviser and strategist at Ghost Group, an operating company that specializes in marijuana technology companies, echoes Piper’s optimism. After spending more than 11 years on the issue, Houston and his colleagues believe that recent poll numbers—showing that a majority of Americans approve of medical marijuana—bode well for a victory. “We’re at a tipping point right now,” he said the vote that appeared ready to come Thursday night. “We’ve got a status quo that isn’t working—it’s a huge mess.”

While President Obama has spoken openly of his support for medical marijuana, its classification as a Schedule I substance gives fed officials the freedom to continue prosecuting. “The DEA—they’re the last people in this, they are taking no prisoners,” Houston said. “Our side says if you’re going to keep fighting the war on drugs, fine. But let’s take the sick and dying out of this, at the very least.”

A large part of Houston’s confidence in the amendment getting the 218 votes it will need to pass stems from Rep. Jared Polis. After first meeting Polis through Colorado politics in 1998, Houston says he’s witnessed the congressman's views transform. “Jared is indisputably the master of interest in Congress. I have seen him grow in his understanding of this, he has really mastered the politics and the intricate nature of this topic.”

But Polis isn’t alone. Six Democrats and six Republicans in the House will be standing behind the bill as co-sponsors Thursday night. Armed with anecdotes, such as the families of epileptic kids flocking to Colorado for the healing powers of a cannabinoid oil dubbed Charlotte’s Web, they’ll fight to persuade their colleagues that waging war on the sick and dying isn’t just ill-advised—it’s senseless.

If Congress ever had a chance to redeem itself, or at least in the majority of Americans’ minds, that time would be now.