Republicans have failed to muster enough votes to overrule U.S. President Barack Obama's recent veto of a bill that would have approved the Keystone XL pipeline.

A vote that would have overridden Obama's recent veto lost 62-37 on Wednesday. The move was not a surprise — proponents of the bill had telegraphed in advance that they doubted they had the two-thirds majority (66 votes) that would have overruled his decision.

"If we don't win the battle today, we will win the war because we will find another bill to attach this pipeline to," said North Dakota Republican Senator John Hoeven, the chief sponsor of the bill that would have effectively taken the decision on the pipeline out of the president's hands.

The $8 billion, 1,800-kilometre pipeline, proposed by the TransCanada Corporation, would bring 800,000 barrels of Canadian oil to refineries on the U.S. Gulf Coast every day. It is proving to be one of the major political footballs of the year leading up to the 2016 presidential election, when there will be someone new elected to the White House.

The project's backers say it will create jobs and bolster American energy self-sufficiency, while opponents have largely rallied against Keystone based on environmental grounds.

"Senate Republicans have shown just how out of touch they are with the priorities of American families with their repeated attempts to force approval of the Keystone XL tarsands pipeline," the Sierra Club's executive director Michael Brune said. "The decision to deny this dangerous project belongs to President Obama alone, and we are confident he has all he needs to reject it once and for all."

For his part, Obama has said all along that the bill circumvented the well-established process for approving cross-border pipelines, which must be determined to be in the national interest.

The Keystone XL bill was only the third time in his presidency that he has vetoed a bill.