On Wednesday, the Senate Committee on Environment and Public Works met to vote on whether to advance the nomination of Scott Pruitt — President Trump’s pick to lead the Environmental Protection Agency and a staunch opponent of basically everything Obama’s EPA did on climate change.

Except for one hitch … no Democrats actually showed up to the vote. The dais was half-empty, and the committee eventually had to adjourn without reaching a decision. (The committee will try again on Thursday to advance Pruitt’s nomination — the full Senate would then have to vote to confirm him.)

The committee is half full / the committee is half empty. pic.twitter.com/8FOILNYV1j — Alex Guillen (@alexcguillen) February 1, 2017

A move like this isn’t unprecedented. Back in 2013, Republicans on this committee boycotted the vote to advance Gina McCarthy, Obama’s pick to lead the EPA. After delaying the nomination for 136 days, the GOP finally relented when McCarthy agreed to certain conditions, such as creating an expert panel on economic modeling.

So what do Democrats want? Answers. In a letter to the committee, Ranking Democrat Tom Carper of Delaware complained that Pruitt had failed to answer many of the questions Democrats had submitted in writing about his potential conflicts of interest and industry ties. Until Pruitt gave them more info, the boycott would stand.

Why Democrats are concerned about Pruitt

Before Pruitt was tapped to lead the EPA, he was attorney general of Oklahoma, where he reportedly had close ties to the fossil fuel industry, as detailed by the New York Times in 2014. While there, Pruitt also sued to overturn a number of key Obama-era regulations on climate change. (He’s lost all those cases in court so far.) Now he’d be in charge of the agency responsible for environmental protection.

So Democrats wanted to probe these ties further. As Carper’s letter notes, Sen. Ben Cardin (D-MD) had asked Pruitt for all of his communications with agribusinesses as part of water-quality litigation he did for the state. Pruitt basically told Democrats to go file a request with Oklahoma if they wanted it:

Senate Democrats also complained that Pruitt had declined to say whether he’d recuse himself in EPA decisions involving matters that he’d previously sued the agency over. "His responses," the letter said, "have not answered whether or not he will do so."

On Twitter, Carper further railed against Pruitt:

The @EPWDems asked Scott Pruitt to name any @EPA protection he supports. He couldn't name one. — Senator Tom Carper (@SenatorCarper) February 1, 2017

Scott Pruitt has sued the @EPA over 20 times. As our next EPA Administrator, would he continue this assault on the agency from the inside? — Senator Tom Carper (@SenatorCarper) February 1, 2017

The @EPWDems asked Scott Pruitt to provide documents & prove that his industry ties would not affect his leadership at the @EPA. He refused. — Senator Tom Carper (@SenatorCarper) February 1, 2017

When @EPWDems asked Scott Pruitt for information, he told us to go to the back of a 2-year line for information requests at his office — Senator Tom Carper (@SenatorCarper) February 1, 2017

Scott Pruitt's record attacking the @EPA raises serious concerns. His unresponsiveness to simple questions has only heightened our concerns. — Senator Tom Carper (@SenatorCarper) February 1, 2017

Republicans have dismissed this all as political theater over a nominee that liberals and environmentalists object to on policy grounds. Sen. John Barrasso (R-WY), who chairs the committee, said Pruitt had already been subjected to one of the longest Senate confirmation hearings since 2001 — six hours in all. “The hearing was fair,” Barrasso said at today’s meeting. And Democrats may not have liked Pruitt’s answers to their follow-up questions in writing, Barrasso said, “but he's given them answers."

It’s unclear what happens next. Democrats had also been boycotting committee votes for Tom Price (Trump’s health secretary pick) and Steve Mnuchin (his Treasury pick). But on Wednesday, Republicans on both of those committees simply suspended the usual rules and sent the nominees through to the full Senate, bypassing the boycotts. Republicans could try to do the same thing with Pruitt.

Ultimately, the GOP is in a strong position to push Pruitt through: They have a majority on the environment committee, and almost ever Republican in the Senate has publicly supported Pruitt — with the exception of Susan Collins of Maine, who has said she’s “concerned” about how often he’s sued the agency. The stark divide is a good sign of how utterly polarized the two parties have become on climate and environmental policy.

Still, Democrats don’t seem inclined to let Pruitt sail through without a fight. In recent days, the liberal base has been pressuring senators to vote against all of Trump’s Cabinet nominees — there was even a big protest outside of Chuck Schumer’s house in New York over this last night. In the end, Senate Dems don’t have the numbers to prevent anyone from getting confirmed, but their supporters at least want them to quit making it so easy for Trump.