Senate Kills Colorado Clean Air Resolution Along Party Lines

Why It Matters

The Senate on April 29 rejected a motion to proceed on S.J.Res. 139, a Congressional Review Act resolution that would have overturned the Trump EPA's January 2026 decision to disapprove Colorado's Regional Haze Plan for the second implementation period. The final tally: 46 in favor, 52 against, entirely along party lines.

The EPA's disapproval of Colorado's plan effectively blocks the state's framework for reducing haze-causing pollution near national parks and wilderness areas, keeping in place emissions from coal-fired power plants that the state had sought to phase down. S.J.Res. 139 would have nullified that federal override and restored Colorado's authority to implement its own air quality roadmap under the Clean Air Act's cooperative federalism structure.

The stakes extend beyond aesthetics. Sulfur dioxide, nitrogen oxides, and fine particulate matter, the same pollutants that scatter light and create haze, also carry documented public health consequences. Colorado's plan addressed both. The EPA's disapproval does not.

The Big Picture

The Trump EPA, under Administrator Lee Zeldin, issued its disapproval of Colorado's Regional Haze Plan on January 26, 2026, arguing the state had "put desire to close power plants over federal law." The agency framed the decision as protecting "reliable baseload energy sources" essential to what it called "Powering the Great American Comeback."

Colorado's Democratic senators, Michael Bennet and John Hickenlooper, along with Sen. Sheldon Whitehouse (D-RI), forced the floor vote using CRA procedures, which allow a simple majority to override agency rules but require 51 votes to proceed. They didn't have them.

This was not an isolated maneuver. Democrats have now used the same CRA playbook on a series of regional haze disputes in the 119th Congress. A similar resolution targeting South Dakota's Regional Haze Plan, S.J.Res. 86, failed a motion to proceed in January 2026 by a vote of 43-50. Resolutions targeting Montana (S.J.Res. 119) and Indiana (S.J.Res. 122) remain in committee. The pattern is clear: Democrats are using these votes less to legislate and more to force Republicans on record.

Partisan Perspectives

Democrats framed the vote as a referendum on whether the federal government should be able to override a state's carefully negotiated environmental plan.

Hickenlooper, in a statement following the failed vote, said: "Colorado has consistently proven that we can bring together communities, utilities, and regulators to protect our clean air without hurting our economy."

He added that the vote forced "every Senator to go on record yesterday on whether they support this thoughtless decision."

Rep. Diana DeGette (D-CO-1), who led the Colorado Democratic House delegation in a letter to the EPA, argued the agency's action "undermines Colorado's authority to improve air quality and reduce pollution causing hazy skies in our prized national parks."

Republicans, meanwhile, aligned entirely with the Trump EPA's framing. The Senate's official daily press labeled the resolution the "Bennet Colorado Anti-Electric Reliability CRA," a characterization that signals how GOP leadership communicated the vote to its members. No Republican broke ranks.

The Trump EPA's own press release made the administration's position unambiguous: reliable baseload energy, read coal, takes precedence over state-designed visibility improvement timelines.

No formal White House Statement of Administration Policy was issued on S.J.Res. 139, but the unanimous Republican opposition left no interpretive gap.

Political Stakes

For Democrats, the loss was expected but not pointless. Forcing a recorded vote on a Trump EPA action that overrode a Democratic-led state's environmental plan gives the party a clean data point heading into the next election cycle. Colorado is a state where clean air and outdoor recreation carry genuine political salience, and the vote gives Bennet and Hickenlooper a concrete example of federal interference in state environmental planning.

For Republicans, the vote reinforces their alignment with the administration's energy-first posture, but it also puts every GOP senator formally on record opposing a state-developed air quality plan. That positioning could complicate messaging in states where national parks and tourism economies are central to local identity.

For Coloradans, the practical consequence is that the EPA's disapproval stands. The state's Regional Haze Plan, which Bennet's office described as the product of years of coordination between "communities, utilities, and regulators," is now subject to a federal override that could require renegotiation under terms more favorable to continued coal plant operations.

Worth Noting

Among organizations that lobbied on regional haze and Clean Air Act legislation, American Fuel & Petrochemical Manufacturers stands out for its PAC activity. Its AFPMPAC directed contributions to dozens of members, with heavy support flowing to Republican senators who voted against S.J.Res. 139, including Sen. Shelley Moore Capito (R-WV) at $10,000, Sen. John Barrasso (R-WY) at $7,500, and Sen. Mike Crapo (R-ID) at $7,500. Sen. Steve Daines (R-MT) received $8,500 from the PAC. All voted against the motion to proceed.

FirstEnergy Corp's PAC, which has contributed $296,000 across dozens of members, also directed funds to several senators who voted no, including Capito ($6,000) and Barrasso ($1,500).

None of these contributions are evidence of a quid pro quo, and the vote itself was entirely predictable based on party affiliation alone. But the financial footprint of energy industry PACs among the senators who blocked the Colorado resolution is consistent with the broader alignment between Republican energy policy and fossil fuel industry interests that has defined this Congress.

The Bottom Line

Democrats knew that S.J.Res. 139 was never going to pass when they filed it. The resolution's value was procedural and political, not legislative. It created a moment of accountability on a federal action that, in the absence of a floor vote, might have drawn little national attention.

The 119th Congress has now seen multiple CRA challenges to EPA regional haze decisions, all failing along party lines, all targeting rules that affect coal-dependent energy infrastructure in western and midwestern states. Democrats are building a record. Whether that record translates into electoral consequences remains an open question.

The more durable obstacle for Colorado is the EPA rule itself, which now stands, and which the state would need to challenge through administrative or legal channels to undo.

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