Senators approved the Keystone XL pipeline in a momentous vote Thursday as nine Democrats bucked their party leaders and joined Republicans in backing the long-stalled project, setting up an eventual showdown with President Obama, who has vowed a veto.

The vote marks the first major accomplishment for the Senate Republican majority, who carefully selected the pipeline to put at the top of the agenda in hopes of preparing Democrats for even bigger tests with Mr. Obama.

“This took a bipartisan effort to get done. That’s what the people want,” said Sen. John Hoeven, the North Dakota Republican who sponsored the legislation.

AUDIO: Stephen Dinan with Andy Parks

The 62-36 vote is a high-water mark for the pipeline, which had never before cleared the Senate on a binding vote, and just two months ago fell to a Democratic filibuster.

The bill still must be combined with a House version that passed the chamber this month before it heads to Mr. Obama.

Senate Democrats said they had the votes to sustain a presidential veto and accused Republicans of bowing to the wishes of a Canadian oil company in building the pipeline.

“This bill is a disgrace. It is a disgrace, and it is the first bill they bring up,” said Sen. Barbara Boxer, California Democrat. “This waves every single law that’s important to the American people to protect them. I think this is a scandalous bill.”

Keystone has taken on political significance much larger than the 830,000 barrels of oil per day that will flow through it. For supporters, approval has become a test of whether the U.S. would pursue fossil fuels domestically. For environmentalist who oppose the pipeline, it was symbolic of a country unwilling to confront climate change.

The 1,179-mile pipeline would carry bitumen from tar sands in Alberta to Steele City in Nebraska, where other pipelines would farm it out for refinement.

Mr. Obama says he will veto the bill because he doesn’t want to change current law, which gives his administration the power to make a final decision. He says the pipeline application, first filed six years ago and now pending with the State Department, should not be rushed.

The president also said he wanted to wait until a Nebraska court ruled on a local challenge to the path of the pipeline, but the state Supreme Court threw out the case several weeks ago with an argument that the challengers didn’t have standing.

Opponents say the thousands of jobs created in building the pipeline would be short-term and only a few dozen would be sustained after Keystone is up and running. They also said the pipeline wouldn’t affect the price of gas in the U.S. because the oil would go to the Gulf of Mexico to be refined and likely shipped to other countries.

Supporters counter that the oil would be drilled in Canada regardless of Keystone. If the U.S. doesn’t build the pipeline, they say, the oil will be shipped to China or elsewhere and the carbon emissions will be the same. They argue that more oil in North America is good for price stability and helps free the U.S. from dependence on Middle East fuels.

The nine Democrats who sided with Republicans to approve the pipeline were Sen. Michael F. Bennet of Colorado, Sen. Thomas R. Carper of Delaware, Sen. Robert P. Casey Jr. of Pennsylvania, Sen. Heidi Heitkamp of North Dakota, Sen. Joe Manchin III of West Virginia, Sen. Claire McCaskill of Missouri, Sen. Jon Tester of Montana and Sen. Mark R. Warner of Virginia.

Senate Minority Leader Harry Reid, Nevada Democrat, and Sen. Marco Rubio, Florida Republican, missed the vote.

Story Continues →