At a news conference Wednesday, senators from both parties said the Nebraska decision leaves Obama with no other choice but to approve the pipeline, which would carry up to 800,000 barrels of oil a day from tar sands in western Canada to refineries in Houston and other Texas ports. The pipeline also would travel though Montana, South Dakota, Nebraska, Kansas and Oklahoma.
"No more excuses. It's time to put people to work," Baucus said.
"Back home, we call this a no-brainer," added Sen. Joe Manchin, D-W.Va.
Hoeven, of North Dakota, said the tar sands oil will be produced whether or not the U.S. approves the project. "Our choice is, the oil comes to us or it's going to China," he said.
Nebraska's approval of the pipeline means all six states along the proposed route now support the project, said House Speaker John Boehner, R-Ohio. Majorities in the House and Senate also have endorsed the pipeline. National polls repeatedly show a majority of Americans back the project.
Boehner said he recognizes the political pressure Obama faces from environmental groups and other opponents, but said "with our energy security at stake and many jobs in limbo, he should find a way to say yes."
White House spokesman Jay Carney said Tuesday that the State Department was reviewing the project and he did not want to "get ahead of that process."
Once that review is completed, "we'll obviously address that issue," Carney said.
Meanwhile, Secretary of State nominee John Kerry said he plans to divest holdings in dozens of companies in his family's vast financial portfolio to avoid conflicts of interest if he is confirmed by the Senate.
Kerry, a Massachusetts Democrat, said he would not take part in any decisions that could affect the companies he has holdings in until those investments are sold off. Among the investments are holdings in two Canadian companies, Suncor and Cenovus Energy Inc., both of which have publicly supported the Keystone XL pipeline. Kerry's investments are in family trusts.
Associated Press writer Stephen Braun contributed to this report.
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