It’s not just last night’s Keystone XL vote, either, although that was a rather telling moment in itself. There may have only been theoretical value in getting Landrieu a legislative win to use in her runoff election less than three weeks from now, but at the moment it’s all Landrieu has for an argument in Louisiana for another term. Even with Barack Obama’s veto pen serving as a backstop, though, only fourteen of her 55 colleagues could bother to lend her that kind of assistance — and those fourteen include four who won’t be part of next year’s Senate anyway. Even the Democratic leadership in the Senate left Landrieu twisting in the wind, which prompted public disgust from Joe Manchin and Heidi Heitkamp, two Democrats that might be on the GOP radar for party switching in the next few weeks as committee assignments solidify.

In truth, though, Democrats had already given up on Landrieu two weeks ago, and maybe longer than that. National Journal reaches the same conclusion, although Lauren Fox and Emily Schultheis spend a lot of time covering the ways in which Landrieu could pull out a surprise win. The likelihood of that coming to pass can be measured by Democratic investment into the race, which is to put those odds at nil:

Landrieu is an endangered species, the last Democratic senator in the Deep South, and she can no longer campaign as the powerful chairwoman of the Senate’s Energy and Natural Resources committee in her oil- and gas-rich state now that Democrats have already lost their majority in the Senate. An internal poll released last week from her Republican opponent, Rep. Bill Cassidy, showed Landrieu down 16 points in the polls. The last 15 public polls have shown Cassidy leading, although most merely by single digits. And, even if Landrieu could have convinced enough of her colleagues to get behind Keystone, it’s unclear how much of a difference such a victory could have made for her. House Republican leaders already allowed Cassidy to lead the charge last week to approve Keystone in the House.

Now, Landrieu faces the task of running a campaign in Louisiana that few in Washington believe she can win. After 18 years in the Senate, it looks like this is a campaign that Landrieu will finish off alone.

At this point, her party isn’t swooping in to save the day: National Democrats have pulled the plug on her race. With roughly $10 million in debt from the 2014 election cycle and a pile of losses from Arkansas to Colorado, the Democratic Senatorial Campaign Committee canceled roughly $2 million in television advertising spots it had reserved when Landrieu’s runoff race was still seen as competitive or possibly the deciding race for control of the Senate.

Maybe if Republicans made a mistake in easing off the gas pedal, it might give Landrieu an opening, but … that’s not happening either:

The Republican National Committee, meanwhile, is revving up its turnout machine and coalescing around Cassidy. Even Cassidy’s primary opponent, Rob Maness—who earned 14 percent of the primary vote on Election Day, has appeared at “unity rallies” to show his support. High-profile conservatives like Sen. Rand Paul of Kentucky and former Alaska Gov. Sarah Palin have appeared with Cassidy to show their support. The RNC dispatched 300 volunteers to Louisiana to knock doors and campaign for Cassidy, and the National Republican Senatorial Committee still plans to spend between $1.5 million and $2 million on the race.

Even pollsters seem to have given up on this race. The only survey results that have been published are an internal Cassidy poll (+15) and a survey from newcomer Gravis Marketing (Cassidy +21). The money imbalance is what made the vote yesterday so important to Landrieu — it was an inexpensive way to validate the last argument that she had about her clout in Washington for Louisiana. That would have cost her colleagues nothing except a meaningless vote, and Landrieu couldn’t even get the bill across the finish line. Her opponent, meanwhile, got the same bill passed easily in the Republican-led House, which reinforced Cassidy’s argument at Landrieu’s expense: it will be better to have a majority Senator on the Energy Committee than a ranking minority member.

Aaron Blake called the Keystone vote Landrieu’s “final indignity”:

This was basically Landrieu’s final play. With no party funding for her campaign, she has been drubbed on the airwaves — as in, exponentially so. And even before that, few gave her much hope in her runoff with Rep. Bill Cassidy (R-La.).

So in a last-ditch effort to move the needle, she launched the Keystone campaign. Nevermind that the very same bill will probably pass with ease once Republicans take control of the Senate in January. She wanted to prove she could make it happen two months earlier — because why not.

And Senate Democrats — who, again, have abandoned her financially — have now abandoned her in spirit too. The vote wasn’t just meaningless because Republicans will pass the bill come next year; it was also meaningless because the White House has basically said it would veto the bill, as the State Department is still reviewing the project.

And despite all of it — despite the whole dog-and-pony show of the past week — Democrats couldn’t even give Landrieu enough votes to breathe a little life (hypothetically, at least) into her long-shot campaign.

Yahoo News also points out that the flop has made an impossible race even worse:

A failed effort to push approval of the Keystone XL pipeline through Congress behind her, Louisiana Sen. Mary Landrieu now faces an even greater challenge to win a runoff election next month.

After narrowly leading the field on Nov. 4 as her party lost control of the Senate, Landrieu had pinned her bid for re-election on championing approval for the long-delayed Canada-to-Texas pipeline during the lame-duck Congress. While the pipeline would not pass through Louisiana, it would serve as a ready-made example of her clout in Washington for voters in a state with a robust oil and gas industry.

“I took to the floor of the United States Senate and used the power that comes from being a senator representing one of the great states in this nation to force a debate on an issue that I felt strongly about,” Landrieu said not long after she and pipeline supporters in the Senate fell one vote shy of the 60 they need the advance the measure.

Complicating matters was the fact that Landrieu’s runoff opponent, GOP Rep. Bill Cassidy, is able to tell voters that the Keystone XL pipeline bill he authored was approved with ease in the Republican-led House. “The Senate should have approved it today,” Cassidy said in a statement. “It should have approved it six years ago.”

Even when it cost Democrats next to nothing to come to her rescue after six years of Landrieu’s inattention on Keystone, they couldn’t be bothered. That should make Landrieu’s “clout” in Washington very clear indeed for Louisiana voters.