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The Keystone pipeline debate in 2 mins
01:47 - Source: CNN
Washington CNN  — 

Senate Democrats blocked an effort by Republicans to end debate on a bill to approve the Keystone XL pipeline, a setback for GOP leaders who must rely on a handful of Democrats who have supported the project in the past in order to get approval of their top legislative priority of the new Congress.

60 votes were needed on a pair of procedural motions to end Democratic filibusters, but each failed on a 53-39 tally.

READ: Keystone debate ends with Democrats’ ire

Democrats who voted against moving to a final vote on the bill said they were frustrated Senate Majority Leader Mitch McConnell prevented debate and votes on amendments during a tense late-night session on Thursday that short-circuited what otherwise appeared to be actual bipartisan progress on the contentious issue.

“I’m very disappointed,” Sen. Tom Carper, D-Delaware, a Keystone supporter, said as he headed to the floor to vote no. “I’m still not sure why that happened.”

The vote was significant for Democrats who pointed to it as proof Republicans will need to reach across the aisle to get things done.

“Sen. McConnell promised Democrats an open amendment process and a full-throated debate on the Keystone pipeline and we are holding him to that promise,” said Sen. Chuck Schumer, D-New York, a Keystone opponent. “Trying to muzzle the debate by refusing to allow Democrats even one minute to advocate for their amendment and then simply refusing to hold votes on dozens of amendments is not remotely an open process.”

Republicans saw it differently. They pointed to the more than two dozen votes on amendments from both parties as evidence they are running a much more accommodating Senate than the one they faced when they were in the minority for the last several years.

“We’ve had a lot of floor discussion. We’ve considered Democrat and Republican amendments,” McConnell said before the vote.

“I’m calling on all of my colleagues – especially the co-sponsors of this bipartisan bill, especially those who’ve supported Keystone without any amendments in the past – to vote for jobs and progress tonight, not the kind of gridlock American voters just rejected so emphatically,” he said.

Only four of the nine Democrats who voted with Republicans to begin debate voted with them to end it. They were Joe Manchin of West Virginia, Joe Donnelly of Indiana, Michael Bennet of Colorado, and Heidi Heitkamp of North Dakota.

RELATED: Keystone crunch time

“Congress needs to work together, which includes robust debate, calling up amendments, and voting,” Heitkamp said after the vote, urging debate to resume on the bill.

Sen. Lisa Murkowski, R-Alaska, the chairman of the Energy and Natural Resources Committee, who is the floor manager of the bill with Democrat Maria Cantwell of Washington, said the two would get back to work to reach an agreement on amendments that would satisfy both sides.

“Perhaps we can work towards an agreement that will allow for additional amendments to be processed but ultimately an agreement that will allow us to get to passage of the Keystone XL pipeline,” she said.