Senate Majority Leader Mitch McConnell became the latest and highest-ranking legislator to come out against the Federal Communications Commission’s set-top box proposal Friday, asking Chairman Tom Wheeler to “reconsider moving forward” with making pay-TV providers content available on third-party devices.

Beyond being the Senate’s leading man, McConnell said his concern chiefly stems from representing the rural state of Kentucky and it’s smaller cable providers, who many on both right and left fear will see their cost rise and profits fall if their content is made available on third-party navigation devices at no extra cost.

“Rather than applying a light regulatory touch, the FCC would require existing programming distributors to provide the copyrighted programming they have licensed from content providers to third party manufacturers and app developers, none of whom would be bound by the agreements to protect this content,” McConnell wrote in a letter to Wheeler and the other four commissioners Friday.

The majority leader echoed the concerns of Republican FCC Commissioner Ajit Pai and others that the mandating pay-TV providers to make their content available on third-party boxes could mean more infrastructure costs for providers, which could disproportionately hurt smaller cable networks.

Wheeler’s rulemaking instructs multichannel video programming distributors (MVPDs) to agree on a standard video format for easy integration in third-party boxes. Accoding to Pai, MVPDs are unlikely to come to an agreement, potentially necessitating the need for additional hardware — or even a second box in subscriber homes — to transmit content.

“Even absent these new proposed mandates, providing video services in a rural area poses many challenges,” McConnell wrote. “As a number of Kentucky distributors have noted, the rural geography means higher costs to deploy fiber and their small customer bases means they frequently pay higher costs for content.”

In the months since the rulemaking was advanced at the FCC, McConnell said he’s heard from “hundreds in Kentucky” concerned about the proposal’s potential to raise prices for rural cable.

Democrat Sens. Ed Markey of Massachusetts, Richard Blumenthal of Connecticut and House California Democrat Rep. Anna Eshoo held a press conference Thursday to stump for the proposal, which was precipitated by a study out of the senators’ offices that found the average U.S. household spends $231 annually in set-top box rental fees, pulling in almost $20 billion every year for providers.

House appropriators on the same day passed a Financial Services and General Government appropriations bill to, among other things, mandate the FCC to hit pause on the set-top box proposal until the agency completes a study to gauge its economic impact.

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