There isn’t much room for optimism among progressives these days. The president’s avenues to legislative achievement in his final two years are narrow and seem mostly to lead to the right — toward a corporate tax reform in one instance, and a NAFTA-style trade deal with the Asia-Pacific region in another.

But in these dark days, there is, as we are already witnessing, reason for hope — in the form of a landmark climate change deal with China last week and an expected executive action on deportations very soon. And today, increasingly, there are signs that the United States could make greater strides on criminal justice reform than at any time in a generation or more.

From a moral standpoint, the need to reform the justice system is clear. During the past four decades, the U.S. prison population has quadrupled even as the crime rate has dropped. We have some 2.4 million people behind bars, far more than any other country, costing about $80 billion a year to maintain. Worse yet, as result of racial disparities in sentencing, more than half of U.S. prisoners are minorities. These staggering statistics stem from the failure of the “war on drugs,” the true impact of which can only be measured in destroyed lives and devastated communities, especially among the most marginalized segments of society.

From a political perspective, the issue unites people along “transpartisan” lines — not a centrist-style compromise, but a cause that aligns with the priorities of both parties for different reasons. For progressives, mass incarceration is not merely a legal problem; as Michelle Alexander describes in “The New Jim Crow,” it is a civil rights crisis. Two-thirds of the Republican Party’s fabled three-legged stool support reform, too: fiscal conservatives, from a budgetary perspective, and religious conservatives, increasingly, from a moral one. In 2010, for example, a conservative reform initiative called Right on Crime launched with the support of Republicans including Jeb Bush, Grover Norquist, Tony Perkins and Ralph Reed. And though the issue has not yet broken through the gridlock in Congress, a growing number of Republicans are abandoning the party’s traditional tough-on-crime posturing.

Earlier this year, Sens. Cory Booker (D-N.J.) and Rand Paul (R-Ky.) teamed up to introduce the REDEEM Act, a comprehensive bill that aims to keep children out of the adult criminal justice system and incentivizes states to seal the records of nonviolent offenders. Meanwhile, Sens. Dick Durbin (D-Ill.) and Mike Lee’s (R-Utah) Smarter Sentencing Act, which would reduce certain mandatory minimum sentences and allow judges more discretion in nonviolent drug cases, attracted 30 cosponsors. Congressional aides expect Paul to continue pressing the issue in the next Congress, which may create additional momentum for reform as he moves toward an expected presidential run.

Indeed, across the country, public support for criminal justice reform is becoming increasingly clear. Midterm voters in Alaska, Oregon and Washington, D.C., approved the legalization of marijuana, which will help protect thousands — particularly minorities, who are disproportionately arrested for simple possession. New York police recently announced that they will stop making arrests for simple marijuana possession. And California voters overwhelmingly passed a ballot initiative, Proposition 47, that reclassified a number of nonviolent and drug-related felonies as misdemeanors and is expected to affect about 40,000 offenders a year. The campaign for Proposition 47 brought together a diverse collection of supporters, including rap icon Jay Z, Newt Gingrich, the American Civil Liberties Union and conservative billionaire B. Wayne Hughes.

Looking ahead, criminal justice reform could become an important issue in both parties’ primary contests. The likely Republican contenders include Sen. Marco Rubio (R-Fla.), a vocal critic of reform who recently railed against “careless weakening of drug laws that have done so much to help end the violence and mayhem that plagued American cities in prior decades.” On the Democratic side, one of former secretary of state Hillary Clinton’s opponents may be former senator Jim Webb (Va.), who worked to create a commission — which Republicans blocked — to tackle mass incarceration. If Webb continues making noises about running in the Democratic primary, Clinton will face increasing pressure to address his signature issues, with criminal justice reform near the top of the list.

Whatever happens in the next two years, however, the movement for criminal justice reform is not going away. This month, the ACLU announced an ambitious plan to force the issue into the electoral debate, with the goal of cutting the incarceration rate in half in eight years. George Soros’ Open Society Foundations contributed $50 million to support the campaign, the largest grant in ACLU history. While any connection to Soros, a longtime boogeyman of the right, would typically send Republicans running, the billionaire Koch brothers have also shown support for criminal justice reform initiatives, such as Families Against Mandatory Minimums. This coincides with the launch of the Marshall Project, a nonprofit newsroom headed up by Bill Keller, formerly of the New York Times, which will focus on criminal justice issues.

The odds are still against any major legislation passing in 2015. There are partisan battles brewing over immigration and the budget, and Republicans may well revert to their favored strategy of all-out opposition to the president. Still, criminal justice reform is one of those rare instances where moral decency, popular opinion and political incentives all align. For progressives, who see few opportunities for near-term victories at the federal level, this is a winnable fight — and one very much worth fighting.

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