Jacquelyn Martin / AP

As President Donald Trump descends on the border Thursday to further make his case for a wall, back home in Washington congressional Republicans—the ones whose resolve he needs if he’s going to continue his shutdown campaign—are growing more anxious. While the images Trump broadcasts to the nation may bolster his case to his base, these Republicans are left to talk and share doubts among themselves.

A handful of Republican senators have so far signaled their willingness to reopen parts of the government without funding for a border wall now that the partial government shutdown is tied for the second longest in the country’s history, with no end in sight. Those Republicans include Senators Cory Gardner of Colorado, Susan Collins of Maine, and Lisa Murkowski of Alaska, who told reporters on Tuesday that Congress “can focus on [Trump’s] very legitimate concerns about border security … through the Homeland Security appropriations bill” and “in the meantime, let’s allow for these other departments to do the work.”

The GOP response to all of this is crucial to ending the impasse. With enough members, Senate Republicans could potentially persuade Senate Majority Leader Mitch McConnell—and indirectly, the president—to take up legislation reopening parts of the government without the inclusion of border-wall funding. Perhaps more likely, worried Republicans could try to pressure Trump to find another way out of the mess—maybe by declaring a state of emergency in order to unlock funding for the border wall, a move that would almost certainly be met with legal challenges from Democrats. Republicans shifting on the issue may also reflect what they’re hearing from their constituents, indicating to Trump that there’s a potential voter rebellion on its way.

In a political world where government shutdowns have become commonplace, lawmakers from both parties have never quite been here before.

And pressure is mounting. Friday will mark the first day that federal workers won’t receive a paycheck. Transportation Security Administration agents have been calling out sick at higher rates since the shutdown began, and furloughed federal aviation-safety inspectors are holding up signs at airports warning passengers that their airplane might not have been properly inspected. If the shutdown continues after February, some 38 million American food-stamp recipients could be at risk of going hungry.

This, in a nutshell, is where we are: After Trump’s highly anticipated Oval Office address on Tuesday, which yielded no new arguments for the border wall, and his two fruitless negotiating meetings with Republican senators and Democratic leadership on Wednesday, the terms of the shutdown debate remain stagnant.

The partial shuttering of the federal government has furloughed 380,000 federal workers and forced 420,000 to work without pay, and it doesn’t seem likely to end soon: Trump has not budged on his demands for $5.7 billion in funding for a border wall, and neither have Democrats in their refusal to offer it.

House Democrats, under the leadership of Speaker Nancy Pelosi, passed legislation last week to fund most of the government through the end of September and the Department of Homeland Security through February 8, but without including money for a border wall. McConnell has pledged not to bring the legislation to a vote unless Trump indicates that he will sign it, making anything that passes the House, at this point, essentially moot.

While the House legislation likely won’t be taken up in the Senate, it’s notable that eight Republicans split with their party to pass it. “I think building a concrete structure sea to shining sea is the most expensive and least effective way to do border security,” Republican Representative Will Hurd, whose Texas district contains more of the southern border than that of any of his House colleagues, told CNN on Wednesday.

Even if McConnell agreed to put the legislation reopening parts of the government to a vote, as of now there don’t appear to be enough Republicans willing to pass it—let alone override the veto it would likely receive from the president. Perhaps that’s why Trump, who has no further negotiations scheduled with congressional leaders, has left one option on the table: declaring a state of emergency.

“If this doesn’t work out, I probably will do it,” Trump told reporters on Thursday, before leaving for a visit to the border town of McAllen, Texas. “I would almost say definitely.”

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