Even as Washington is on the brink of a government shutdown, this bitterly divided Congress just overcame years of opposition and passed a sweeping criminal justice bill that brought the far left and the far right together.

The legislation—dubbed the First Step Act—is aimed at curbing the nation’s mass incarceration crisis through offering some nonviolent inmates the opportunity to earn credits towards an early release if they get an education or take other steps to get them ready for reentering society.

It also ends the decades old racist sentencing law that carried insanely stiffer penalties for the crack cocaine preferred by more black people than the powder cocaine snorted at suburban country clubs or other seedy establishments where white people hang out. It also gives judges and prison officials more discretion when it comes to certain nonviolent crimes, but proponents failed to end mandatory minimum sentences on this go-round.

The legislation was once thought controversial—even a third rail to some of the politicians who helped pass the tough-on-crime bill under Bill Clinton in the '90s—but on Thursday it sailed through the House with the support of 358 lawmakers, as a mere 36 opposed it.

As the measure now awaits a presidential signature, supporters are sensing it’s a new day in Washington when it comes to the nation’s outdated justice system.

“This is historic,” Sen. Cory Booker (D-NJ), who was a critical part of negotiations, told The Daily Beast. “It’s the first time in generations that instead of going in the wrong direction on criminal justice bills, we actually have stopped, turned around and taken a step in the right direction.”

Booker is eyeing a White House run and this measure he helped usher through the Senate on an eye-popping 87-12 vote is expected to be a main part of his pitch to voters.

“As the only senator who lives in a black and brown inner city, this is going to disproportionately affect those communities that have been churned into a system that lacked heart and has lacked judgement and proportionality and it’s going to give more of that back through the system,” Booker said.

For the past five years the junior senator from New Jersey has teamed up with conservatives like Sens. Rand Paul (R-KY) and Chuck Grassley (R-IA)—the chair of the Judiciary Committee—to whip up support while also beating back the legislation’s aggressive foes. And those opponents fought til the end, including Sen. Tom Cotton (R-AK) who last week accused the bill’s supporters of enabling predators.

“If other senators want to vote for a bill that’s going to let sex offenders and child pornographers and wife-beaters out of prison, that’s their prerogative,” Cotton told The Daily Beast. “That’s between them and the voters in their state. I’m not going to vote for that.”

Cotton had previously teamed up with former Sen. Jeff Sessions (R-AL), before he became attorney general (and before he was ingloriously shoved out by Trump), to kill a similar bipartisan effort. And there are still some lingering hardliners in the GOP who are raising the specter that the measure will bring with it additional costs to society, like on the hypothetical victims of any prisoner who goes back to crime.

“We need to look at the other side of this equation,” Rep. Steve King (R-IA) told The Daily Beast. “We know that there will be more people who will be victims of crimes and you can go through the whole spectrum of crimes, so I’m saying this is not thought out.”

The fearmongering accusations that the legislation will surely lead to former prisoners committing crimes on the outside were rebuffed by supporters like Sen. Lindsey Graham (R-SC) who is the incoming chair of the Judiciary Committee.

“That’s probably true, but what I hope you’ll realize is that most people who get out under this bill a bit early are going to contribute mightily to lowering the cost of our prison system,” Graham told reporters at the Capitol after it passed. “To those who say: ‘You should never let them out.’ That ain’t working.”

But Graham also contends that the new measure flipped the script because it is intended to equip prisoners with the tools to become functioning and contributing members of society.

“Here’s the biggest effect of this bill: People are going to get out of jail and they’re far less likely to go back, because they can get out earlier if they work hard and invest in the skill set to stay out,” Graham continued.

“I think that would be a major step in the right direction—mandatory minimums are inherently problematic because at some point they will require a judge to impose a sentence that just doesn’t make any sense at all,” Rep. Bobby Scott (D-VA) told The Daily Beast. “That has loaded up our prisons and is a major factor in mass incarceration.”

However, appetite for a Second Step Act will be hard to find in the next Congress.

“Now we get into a little bit more of the contentious stuff,” Rep. Doug Collins (R-GA) told The Daily Beast of the many prosecutors and police officers who push back on those efforts. “They view it more as, we catch them and you’re being soft on them.”

No proponents are starting to prepare for round two in the new year.

“I do see the bill as being appropriately named the First Step Act—I think there’s more that needs to be done,” Sen. Mike Lee (R-UT) told The Daily Beast.

A remaining goal for many proponents of criminal justice reform remains legalizing marijuana nationally, because tens of thousands of people remain behind bars for something that’s now legal in more than half of the states. Others also want to end the distinctly American phenomenon of private prisons that are used to turn a profit—some are even traded on the stock exchange.

“The second step is to learn from this experience,” Sen. Dick Durbin (D-IL), the number two House Democrat, told reporters after the bill passed. “And to find a way to reduce incarceration while still reducing the crime rate in America.”