Political action on approval of the final phase of the Keystone XL Pipeline is likely done for the year after the Senate fell five votes short of invoking cloture on an energy bill to which Republicans were trying to attach an amendment that would approve construction on Keystone. The Hill reports:

The Senate standoff left green groups confident that Keystone would not be approved this year, and that it was dead for the rest of the Obama era.

"Keystone is not going to become law under this president," Daniel. J Weiss, a senior fellow at the Center for American Progress, told The Hill on Monday.

Even supporters of Keystone acknowledged Monday's vote was a blow.

Sen. John Hoeven (R-N.D.) said the failure to attach a Keystone amendment to the efficiency bill "makes it tougher" to get a deal, especially in an election year. While Republicans are largely united in support of Keystone, Democrats aren't united in opposing it, with those facing re-election in November appearing to be tempted to support it. Several unions have also come out in favor of the pipeline. Sen. Mary Landrieu (D-La.), who is up for election in November and says she supports the Keystone pipeline, blamed Republicans for yesterday's failed votes.

Democrats offered a vote on the Keystone amendment to the energy bill but refused to allow other amendments to be voted on. Senate Minority Whip John Cornyn (R-Tex.) likened Democrats' refusal to allow more Republican amendments to be considered for the Democrat-sponsored energy bill to a "dictatorship shutting out the voices of millions of Americans."

While the Keystone pipeline as an issue has helped galvanize a wide array of political groups attached not just to the Keystone pipeline but issues like the environment and energy independence.

Writing for The Daily Beast, Claire Casey called Keystone America's "dumbest debate," explaining:

From the start, the fight about Keystone XL has been symbolic. As captured by Ryan Lizza in his terrific September 2013 New Yorker article on the topic, Kate Gordon, a leader of the anti-Keystone movement explains, "The goal is as much about organizing young people around a thing. But you have to have a thing." The environmental community, reeling from the failure of cap and trade, needed a fight around which to coalesce. Blocking approval of the Keystone XL pipeline, the "tipping point in the fight against climate change," became the rallying cry.

But the numbers just don't add up. In its most recent Environmental Impact Assessment, published in January, the State Department found (for the second time) that the pipeline would not have a meaningful impact on emissions. Anti-Keystone crusaders point to the relatively higher emissions profile of Canadian oil sands (5—15%, depending on your point of comparison), but even if you were to assume that blocking the pipeline would block the flow of crude into the market, the emissions impact would be about a quarter of 1 percent of the U.S. total. Neither, writes Casey, would approving the pipeline be a "panacea" for energy independence or long-term job creation. Instead:

Keystone XL should be approved not because it will save the U.S. economy, but because it is a large private investment in our country with de minimis negative impacts on the climate, and local safety and environmental issues which can and should be managed and regulated. The Obama Administration first punted on approving or denying applications related to Keystone pipeline construction ahead of the 2012 election, and did so again ahead of this year's elections. This time, the clock was stopped nominally to allow litigation in Nebraska to resolve itself first. That litigation involves eminent domain claims and whether that state's governor, Republican Dave Heineman, followed the correct procedure to seize private land using eminent domain and open it up for pipeline construction. The White House has not taken a stance on the use of eminent domain in constructing the pipeline, only saying the segment in Nebraska needed to pass an environmental review (it has once, before another was ordered).