Washington — The Keystone XL pipeline emerged once again Wednesday as a flashpoint in the race between Democrat Mary Landrieu and Republican Bill Cassidy for the U.S. Senate from Louisiana, with both sides jockeying for position in Congress on the same side of the issue.

Landrieu and Cassidy finished 1-2 in the Nov. 4 open primary, but both were short of the majority needed for outright victory then, and will meet in a Dec. 6 runoff. It’s the last Senate seat to be decided in an election year in which Republicans on Nov. 4 gained more than the six seats they needed to seize control of the U.S. Senate in the new Congress convening in January.

Both Landrieu, a three-term incumbent, and Cassidy, a Baton Rouge congressman, support completion of the northern link of the pipeline, which would bring tar-sands oil from Canada to refineries on the Texas Gulf Coast. It has nonetheless served as a point of contention in the election, with Landrieu claiming credit for using her clout as chair of the Energy and Natural Resources Committee to advance a pro-Keystone bill through the committee this summer, and Cassidy saying her influence is meaningless so long as anti-Keystone members of the current Democratic majority keep the legislation from coming up for a vote on the Senate floor.

The elections Nov. 4 rendered moot the argument over the Senate majority, effective in January. But Landrieu took to the Senate floor Wednesday to urge passage in the lame-duck session of a Keystone greenlight bill by U.S. Sen. John Hoeven, R-N.D., that Landrieu co-sponsored as chairwoman of the energy committee.

“We can do this, “ Landrieu said. “We can pass the Keystone pipeline.

“I’m not asking us to do the impossible.”

Later Wednesday, Senate Majority Leader Harry Reid, D-Nev., announced the Senate will hold an up-or-down vote on the Hoeven bill as early as Tuesday. It will take 60 votes to pass the bill. With all 45 Republicans expected to support it, that means Landrieu will have to get 14 other Democrats to vote yes with her. If that happens, she can point to passage of the bill as an accomplishment in making her case for re-election — and even if the bill falls short, she can say she pushed it to the floor.

Not to be outdone, Cassidy announced that he is introducing a duplicate of the Hoeven bill in the Republican-controlled U.S. House, which has already passed several similar measures that would direct the White House to approve the pipeline. The Republican House leadership is fast-tracking the bill and is set to pass it Thursday. If both chambers pass identical bills, the proposal can go directly to Democratic President Barack Obama for his signature, which is no sure thing.

Supporters of the pipeline say it will create jobs and reduce American dependence on oil imported from unfriendly and unstable foreign countries outside North America. Opponents fear it will result in increased carbon emissions, and the project has been stalled by Obama, whose approval is required because the pipeline crosses an international border. Should he veto a pro-Keystone bill, it is unlikely the current Congress would muster the two-thirds vote in both houses needed to override him.

“It is easy to wonder if the Senate is only considering this because of politics,” Cassidy said in a statement, “even so, I hope the Senate and the president do the right thing and pass this legislation creating thousands of jobs. When I’m on the Senate Energy Committee next year, I will work to ensure the president follows the law and allows the construction of this pipeline.”

In a news conference late Wednesday, Landrieu said, “This is not about credit, it is not about glory, it is not about politics. It is about getting our work done.”

The Cassidy camp drew first blood in the energy-policy bragging match this week when the incoming Senate majority leader, Mitch McConnell, of Kentucky, announced that Cassidy would be appointed to the energy committee if he wins the runoff. A Republican will displace Landrieu as chairwoman in January in any case, but she has argued that if re-elected, she would still wield more influence as the senior Democrat on the committee than a freshman Republican such as Cassidy — who, she said, would be unlikely to land a seat on the committee.

But McConnell undercut Landrieu there by announcing he would, indeed, appoint Cassidy, a Baton Rouge physician.

“I’m confident Dr. Cassidy will use this position to succeed where Sen. Landrieu failed,” McConnell said in a statement included in a Cassidy news release. “One of our top priorities will be actually passing the Keystone XL pipeline.”

In that release, Cassidy said, “Sen. Landrieu made much of her seat on the energy committee, but failed to use that seat to stand up to President Obama’s assault on our energy economy. I’m excited to serve on the energy committee and will use that seat to stand up to President Obama, to deliver a floor vote on the Keystone XL pipeline and to protect Louisiana’s energy industry.”

In a news release late Wednesday, Landrieu’s seat mate, Republican David Vitter, said the timing of Landrieu’s Senate floor speech made it “obvious” the move was “a political stunt.”

Although Obama has not said directly that he would reject the bill, the White House sent strong signals Wednesday that a veto would be likely.

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