The American Civil Liberties Union released an advertisement that will air across Kentucky this week aimed at getting Senate Majority Leader Mitch McConnell to move on consequential changes to the U.S. criminal justice system.

McConnell is being lobbied by Republicans and Democrats on allowing senators to vote on the First Step Act, which looks to reduce mandatory minimum federal sentences for some serious drug offenses.

President Donald Trump used Twitter last Friday to urge McConnell by name to take action on the legislation before year's end. But reports say that Kentucky's senior senator thinks there isn't enough time to address the matter before a new Congress is seated in January.

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In a 60-second spot paid for by the ACLU, a narrator notes how such wide agreement across the political spectrum on a significant issue is rare in Washington, D.C., but that McConnell is dragging his feet.

"The common sense agreement would give inmates who have served their time a second chance at life," the ad says. "It has the support of stalwart conservatives like Chuck Grassley and Mike Lee — and progressives like Dick Durbin and Cory Booker.

"There’s one person stopping it: Senator Majority Leader Mitch McConnell."

McConnell spokesman Robert Steurer repeated a point made previously that senators will review and discuss a new version of the bill this week.

The GOP leader has reportedly promised to conduct a whip count among the 51-member Republican caucus as supporters claim the proposal has well above 60 votes in the Senate.

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But that hasn't satisfied proponents who feel that McConnell is slow-walking the legislation.

"Mitch McConnell is singlehandedly blocking a bill to restore justice for thousands of individuals," said Faiz Shakir, national political director at the ACLU. “The ACLU and our partners in the civil rights community have spent decades fighting for these meaningful reforms, which would change the lives of individuals impacted by mass incarceration, and their families. We can’t allow Senator McConnell to squander this moment; he must give the First Step Act an immediate vote.”

The ACLU plans to spend $10,000 a week on the ad, starting in the heavily Democratic market of Louisville on Tuesday.

Shakir said the goal is to expand it in other parts of the state each week that the bill does not get a vote. He said the radio spot will make it debut in Lexington, another Democratic stronghold, on Wednesday.

The ACLU's ad reminds Kentuckians that their junior senator, Republican Rand Paul, is among those supporters. He and his wife, Kelley, have been conducting a media blitz for the past several weeks advocating for the proposed changes.

Shakir said the goal is to expand it in other markets each week that the bill does not get a vote. He said the radio spot will air in Lexington on Wednesday.

Paul used an interview with Politico last week to call his fellow Kentuckian out, saying if criminal justice reform doesn't pass this year, McConnell will be "singlehandedly stopping criminal justice reform."

First Step is a major effort to reverse certain federal criminal policies that were enshrined into the justice system in the 1980s and 1990s.

Among its most consequential changes is addressing the 100-to-1 sentencing difference between crack- and powdered cocaine-related offenses.

As the ACLU and other proponents of First Step have pointed out, five grams of crack — which is a cheap crystallized version of cocaine — gets a person an automatic five-year prison sentence versus needing 500 grams of powder cocaine, which is a more affluent version of the drug, to receive the same sentence.

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Those who support the measure point out that crack-versus-powder sentencing differences has created racial disparities in federal sentencing, as well.

The bill allows allow inmates locked up under a 100-to-1 ratio to appeal their cases for a reduced sentence based on a compromised 18-to-1 disparity under the Fair Sentencing Act of 2010.

Politically, however, the bill also has created a minor civil war among some of McConnell's most ardent conservatives. Republican Sens. Tom Cotton of Arkansas and Mike Lee of Utah, for example, locked horns this week over how the bill treats sex offenders.

Cotton said in a statement that measure would allow, "early release to multiple categories of sex offenders" and urged senators to slow down. But a Lee spokesman shot back that Cotton was "spreading fake news" about the proposal, and that all federal inmates eligible for early release would first be reviewed by the Justice Department.

McConnell, who has questioned if there is enough time to vote on First Step, is avoiding the public feuds while keeping the focus on Trump's judicial nominations.

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In a tweet Monday, he said the outgoing Congress has a lot to be proud of, "but we aren’t finished yet." He said the Senate has a plate filled with important business that needs their attention before the end of the year.

"We’ll continue to make nominations a top priority, as we have this entire Congress," McConnell said on social media. "The nominees we’ll consider this week are highly regarded and well equipped for public service. I look forward to confirming each of them without further undue delay."

Reporter Phillip M. Bailey can be reached at 502-582-4475 or pbailey@courierjournal.com. Support strong local journalism by subscribing today: courier-journal.com/philb.