The Senate has confirmed former fossil fuel lobbyist Andrew Wheeler as deputy EPA administrator, providing a second-in-command for Administrator Scott Pruitt as he struggles amid alleged ethical failings.

Wheeler was confirmed Thursday with a 53-45 vote. Some Democrats hoped Pruitt’s difficulties would give them the votes to block the confirmation, but their efforts were not enough. Democratic Sens. Heidi Heitkamp of North Dakota and Joe Manchin III of West Virginia joined Republicans in voting for Wheeler. Both are running for re-election this year in states won by President Donald Trump.

“Every West Virginian wants clean air and clean water and I intend to be vigilant in working with the Environmental Protection Agency to ensure that our fundamental environmental protections are implemented in a sound, fair and effective way,” Manchin said after the vote. “I believe that the economy and the environment can and must be balanced. After meeting with Andrew Wheeler, I believe that he will work with states like West Virginia, not against us.”

Wheeler, who has previously worked for the Senate Environment and Public Works Committee, including under former Chairman James M. Inhofe, R-Okla., had an easier process during confirmation hearings before lawmakers familiar with him.

Democrats raised concerns that his ties to the fossil fuel industry could influence his actions at the agency, which they criticize for undoing environmental protections and for lacking transparency under Pruitt. But many acknowledged they knew him from his time with the committee and that they could work with him at EPA.

Asked during his Nov. 8 confirmation hearing whether he would recuse himself from cases involving his former clients, Wheeler first hesitated before conceding.

“I will be recusing myself on any matters where there is a conflict going forward,” Wheeler said.

The stakes for his confirmation rose in recent days as more ethical allegations against his new boss mounted, including lavish spending on flights, expensive hotels and office renovations, and retaliatory actions towards staff who challenged that spending.

‘Dangerous Duo’

Sen. Sheldon Whitehouse, D-R.I., said on the floor before the vote that Pruitt and Wheeler would be a “dangerous duo” given the latter’s previous work on behalf of coal companies. Wheeler has lobbied on behalf of coal firms such as Murray Energy, one of the nation’s largest, and has led consulting firm Faegre Baker Daniels’ energy practice. He is also vice president of the Washington Coal Club.

Environment and Public Works top Democrat Thomas R. Carper of Delaware spoke in opposition to Wheeler’s confirmation on the Senate floor, saying his nomination was “emblematic of an ethically tone-deaf administration,” and that it was important to consider how Wheeler will address Pruitt’s ethical lapses “because it has become clear that my Republican colleagues will not do so.”

“We should be able to hear from Andrew Wheeler what his plans are to rein in the abuses at the EPA before he takes this important job,” Carper said.

Republicans have maintained that Wheeler is the right person to help Pruitt continue undoing the “punishing” regulations of the Obama administration and to tame what they call a runaway agency.

“His wealth of experience at the EPA, on Capitol Hill, and in the private sector have prepared him for this leadership position,” Environment and Public Works Chairman John Barrasso, R-Wyo., said after the confirmation. “Now that the Senate has confirmed Mr. Wheeler, he can get to work advancing policies to protect America’s air, land, water, and communities.”

The position of the deputy EPA administrator had been occupied by an Obama administration holdover, Mike Flynn, in an acting role until April 3 when he retired.

“Andrew Wheeler has spent his entire career advancing sound environmental policies and I look forward to him bringing his expertise and leadership to the agency,” Pruitt said in a news release following Wheeler’s confirmation. “I look forward working with Andrew to implement President Trump’s environmental agenda.”

Watch: Politics and Nominations Abound as the Senate Returns to Washington