LINCOLN, Neb. – Congress is suddenly scrambling to vote on the Keystone XL oil pipeline, but the fate of the oft-delayed $5.4 billion project could still wind up in the hands of an obscure commission in Nebraska that regulates telephones, taxi cabs and grain bins.

The Nebraska Supreme Court is expected to rule within weeks on whether the Nebraska Public Service Commission must review the pipeline before it can cross the state, one of six on the pipeline’s route. Nebraska Gov. Dave Heineman gave the green light in January 2013 without the panel’s involvement.

The commission’s possible role is part of the tangled legal and political history of the pipeline and raises questions about whether it will continue to be snagged even if the Senate votes to approve it next week as expected. The House voted 252-161 Friday to move forward with the project. President Obama, who has delayed a decision pending the resolution of the Nebraska issue, has not said whether he would sign the legislation.

The proposed crude-oil pipeline, which would run 1,179 miles from the Canadian tar sands to Gulf coast refineries, has been the subject of a fierce struggle between environmentalists and energy advocates ever since Calgary-based TransCanada proposed it in 2008.

“I don’t know if they think they can just override Nebraska,” said Randy Thompson, one of three landowners who filed suit to challenge the state’s approval process. “If we win our case, I assume TransCanada is going to have to go back to the drawing board.”