Many of Donald Trump’s cabinet nominations faced vocal opposition from constituents and public interest groups. But well-connected corporate lobbyists stalked the halls of Congress to make sure Trump’s team was confirmed by the Senate, new filings show.

Koch Industries, a fossil fuel conglomerate that owns a variety of business interests that have clashed with environmental regulators, directly lobbied to help confirm Scott Pruitt to head the Environmental Protection Agency.

The firm’s latest disclosure form reports that its in-house corporate lobbying team spent $3.1 million to influence lawmakers over the first three months of the year on a variety of issues affecting its bottom line, including the EPA’s Clean Power Rule on carbon emissions, carbon pricing, the Clean Air Act and “nominations for various positions at the Department of Energy.”

Other groups with a vested stake in the administration’s agenda also disclosed they had lobbied senators to confirm Trump’s nominees.

The American Apparel & Footwear Association, a trade group that lobbies largely on trade and labor standard issues on behalf of clothing manufacturers and retailers, lobbied in support of Andrew Puzder, Trump’s initial pick to lead the Labor Department — and, after Republican senators balked at the fast-food executive, in support of replacement nominee Alexander Acosta. The group’s filing showed it spent $176,485 on advocacy in the beginning of the year, though it did not specify how much of the lobbying total was spent on the confirmation efforts.

“Mr. Puzder has seen, firsthand, the impact of burdensome regulations promulgated by the previous administration, and he has seen both the negative impacts and unintended consequences they can have on employers and employees alike,” a group of business interests including the AAFA wrote in a letter to the Senate.

The National Roofing Contractors Association also lobbied in support of Trump’s labor nominees. The NRCA is a major construction trade group that has opposed new Labor Department rules that require corporations to disclose consultants and law firms hired to influence efforts by workers to engage in labor organizing.

Nestlé, the sprawling food and beverage firm, disclosed lobbying on food safety issues — and the nomination of Sonny Perdue, Trump’s pick to lead the Department of Agriculture.

New York City’s police sergeants union, in a filing listing many issues before legislators this year, noted that it had worked for the confirmation of Jeff Sessions as attorney general. Ed Mullins, the president of the union, wrote to Judiciary Committee members to endorse Sessions as a “man of unquestionable integrity devoted to the rule of law and the best interests of our nation.” The filing shows the union also lobbied for bills to expedite the deportation of alleged gang members and to repeal President Barack Obama’s order limiting the transfer of military equipment to local police departments.

Some groups playing a more subtle role. The Council of Institutional Investors, a trade group representing pension funds, disclosed that its lobbyists had drafted questions for senators to ask during the confirmation hearing of Jay Clayton, the nominee lead the Securities and Exchange Commission.

The confirmation of Pruitt, arguably the most controversial Trump nominee, attracted the most direct support from industry groups.

The American Energy Alliance, an advocacy group founded by former Koch Industries lobbyist Tom Pyle, issued a letter in support of Pruitt along with other Koch-backed conservative nonprofits. America Rising Squared, a political research outfit that has harassed environmental activists, formed a special website — now deleted — to respond to criticism of Pruitt’s record.

Koch Industries has a long and contentious relationship with the EPA. The company’s pipelines were involved in over 300 oil spills between 1988 and 1996, leading to a $30 million fine in 2000, at that point the largest environmental fine in U.S. history. Other Koch subsidiaries have clashed with environmental regulators. Koch’s Pine Bend oil refinery, a major revenue source for the company, spilled up to 60,000 gallons of jet fuel throughout the 1990s.

During the contentious confirmation process, Pruitt, a global warming denier and avowed critic of rules governing industrial polluters, largely dodged questions about his relationship with Koch Industries. Previous reporting revealed that as Oklahoma attorney general, Pruitt joined several Koch-backed lawsuits against EPA rules and remained in close contact with groups financed by Koch’s owners, Charles and David Koch.

When asked about his support from the Koch brothers during the hearing, Pruitt largely demurred, telling Sen. Sheldon Whitehouse, D-R.I., that he did not solicit Koch campaign donations to a group he helped lead. Meanwhile, Koch Industries lobbied to help confirm him as EPA administrator.