Manchin has been a key swing vote on a number of energy and climate related issues.
He was specifically influential in shaping the Inflation Reduction Act, the Democrats’ climate tax and health care bill.
He negotiated with his Democratic colleagues for months, blocking the inclusion of a clean electricity mandate and adding some fossil fuel concessions but ultimately reaching a deal to spur significant renewable energy buildout.
Manchin has also been a key driver in ongoing permitting reform talks and pushed for Congress to mandate the approval of the Mountain Valley Pipeline, which runs through his home state.
The senator was also a driving force behind a 2020 broad bill that touched various pieces of the energy sector and was later incorporated into a government funding deal.
When he was first running for the Senate in 2010, Manchin opposed a Democratic cap-and-trade bill, which sought to curb planet-warming emissions. The bill ultimately did not get a vote in the Senate.
With Manchin out of the race, the chance of his seat being filled by a Republican has significantly increased.
Read more in a full report at TheHill.com.