In a fresh indication that the Republican majority is moving swiftly to approve Keystone XL, Senate Republicans voted down two amendments that Democrats had hoped to attach to legislation approving the controversial pipeline on Tuesday.
Moderate Democrats who support Keystone construction, including Sens. Joe Manchin of West Virginia, Mark Warner of Virginia, and Heidi Heitkamp of North Dakota, joined with every single Senate Republican to cast aside an amendment offered by Democratic Sens. Edward Markey of Massachusetts that would ban the export of all oil transported through the pipeline.
A Republican majority also voted down an amendment from Democratic Sen. Al Franken of Minnesota that would ban the export of all oil transported through the pipeline and require the oil-sands project to be built with American-made steel. Sen. Richard Burr of North Carolina was the sole Republican to vote in favor of the amendment.
The defeat of both amendments brings the Senate one step closer to approving legislation that would green-light construction of the controversial pipeline, despite a looming White House veto threat. It also highlights the weakened position Democrats must now grapple with as the Senate's new minority party.
Republicans took issue with both Democratic amendments, with at least one high-ranking senator calling the pair of proposals a poison pill aimed at sinking the underlying pro-KXL bill.
"Well clearly a lot of Democrats oppose Keystone, so they're adding provisions right now that would make it less likely to pass," Republican Sen. John Hoeven of North Dakota, the sponsor of the Senate's Keystone bill up for debate, said in the Capitol on Tuesday. "These are messaging amendments that Democrats have brought up to distract from the real debate over Keystone," Hoeven said.
In a press conference held Tuesday morning, Democrats cast the amendments as evidence of their commitment to the American middle class, with Sen. Chuck Schumer of New York saying that any GOP opposition to the measures would prove that Republicans are beholden to a "narrow set of special interests."
Ultimately, however, Democrats were not able to overcome conservative opposition to the proposals.
The ultraconservative Club for Growth put pressure on senators to vote against the Franken amendment by signaling it would "key-vote" the measure, while the National Association of Manufacturers notified senators on Tuesday that it opposed the Markey amendment and would key-vote the proposal.
Senate Majority Leader Mitch McConnell has promised a free-wheeling energy debate during his first test of power at the helm of the majority. And Tuesday's series of amendment votes served as the first major test of that pledge.
Republicans say the majority leader has kept his word, but Democrats disagree.
Rather than holding an up-or-down vote on the amendments, the Senate voted to table the proposals offered by Markey and Franken, a move that Democrats say stifled debate.
"Senate Republicans promised an open amendment process, but they are closing off debate, and not allowing a vote on the very first amendment considered by the Senate," Markey said in a statement after the Senate voted to table his amendment.
"I will continue to fight to ensure that if we are going to ask the United States to bear all of the environmental risk of transporting this dirty Canadian oil, we ensure that it is not simply re-exported to foreign nations," Markey added
Republicans defended the vote on Tuesday.
"We did not block a vote," Robert Dillon, a spokesman for Sen. Lisa Murkowski of Alaska, said. "Senator Markey could not get 51 senators to vote for his amendment, and so it was tabled. How is that blocking a vote?"
In a rare spot of bipartisan agreement, however, the Senate voted to approve one Republican-sponsored amendment: a pared-down energy-efficiency proposal offered by Sen. Rob Portman of Ohio and cosponsored by Democratic Sen. Jeanne Shaheen of New Hampshire.
"I am pleased to support this amendment and thank my Republican colleagues from Ohio for his leadership," Democratic Sen. Jeanne Shaheen said on the Senate floor ahead of a vote on the amendment.
Five Republicans opposed the Shaheen-Portman amendment: Sens. Ted Cruz, James Lankford, Rand Paul, Ben Sasse, and Mike Lee.
More controversial amendment votes lay ahead.
Also due up on the bill are a pair of Democratic amendments on climate change. One from Sen. Brian Schatz of Hawaii quotes from the Environmental Impact Statement on climate change science, while the other from Sen. Sheldon Whitehouse of Rhode Island says simply that "climate change is real and not a hoax."
But more are likely -- Schatz told reporters that Democrats had also talked about bringing up an amendment from independent Bernie Sanders on climate change. Eight climate amendments have been pitched on the bill and Democrats Tuesday expressed a desire to vote on as many as possible.
"There's an opportunity for a moderate, science-oriented Republican to show some courage, and vote in the way that they know reflects the facts, even if it may cause them to difficulty in the primary election," Schatz said.
Also due up in the next round of votes is an amendment from Illinois Democrat Dick Durbin on the transportation of petroleum coke.
Cruz has also floated an amendment that would lift the ban on oil exports.
Export lobbyists are privately pressing Cruz not to bring the amendment to a vote, because many Republican senators have not yet taken a stance on the issue.
Cruz told reporters Tuesday that he hasn't decided whether to force a vote on his amendment.
But the Senate's No. 2 Republican hinted on Tuesday that he doesn't think the time is right for a vote.
"There's a legitimate discussion going on about whether that's really ripe for a decision now," said Senate Majority Whip John Cornyn of Texas.
Ben Geman and Jason Plautz contributed to this article