Sen. Joe Manchin III used his perch atop the chamber’s Energy Committee to shine the spotlight Wednesday on a contentious issue that could ease power outages while also jolting the president’s green energy agenda: the fast-tracking of interstate transmission-line projects.

The conservative West Virginia Democrat sought buy-in from lawmakers on both sides of the aisle during a committee hearing Wednesday on whether the nation’s arcane permitting laws should be changed to fast-track energy projects of all forms.

“We should not politicize infrastructure that has long enjoyed bipartisan support. The areas that need the power aren’t just blue states with aggressive climate targets that some of us may not agree with,” said Mr. Manchin, who’s been increasingly critical of what he calls President Biden’s “radical” climate policies as the senator weighs a 2024 reelection bid. “Of course, transmission infrastructure alone isn’t enough for reliability — we also need dispatchable generation like coal, natural gas, hydropower and nuclear.”