President Trump Donald John TrumpOmar fires back at Trump over rally remarks: 'This is my country' Pelosi: Trump hurrying to fill SCOTUS seat so he can repeal ObamaCare Trump mocks Biden appearance, mask use ahead of first debate MORE is facing a potential revolt among Senate Republicans over his decision to declare a national emergency to construct the U.S.-Mexico border wall.

Sen. Rand Paul Randal (Rand) Howard PaulSecond GOP senator to quarantine after exposure to coronavirus GOP senator to quarantine after coronavirus exposure The Hill's Morning Report - Sponsored by National Industries for the Blind - Trump seeks to flip 'Rage' narrative; Dems block COVID-19 bill MORE’s (R-Ky.) public announcement over the weekend that he will oppose Trump’s declaration ensures a resolution blocking it will be approved by the Senate after already passing the House — unless Senate Republicans can find some kind of last-minute way out of the showdown.

Republicans have been hunting for a way out of a fight over the declaration that has badly fractured the caucus, but Paul’s decision underscores the difficulty leadership faces in finding a successful exit strategy.

ADVERTISEMENT

Sen. John Kennedy John Neely KennedyMORE (R-La.), who is expected to oppose a resolution of disapproval, floated that Trump could be rethinking his decision given the likelihood that he’ll have to use his first veto.

“I do think he is probably rethinking the situation,” Kennedy told CNN’s "State of the Union." “I don't think the president has the votes on a straight-up vote to sustain his position. Now, if the Senate says, 'Mr. President, you don't have the authority,' as the House did, I expect the president to veto it, and we will be right back to where we are now.”

Sen. Lamar Alexander Andrew (Lamar) Lamar AlexanderGraham: GOP has votes to confirm Trump's Supreme Court nominee before the election The Hill's Morning Report - Sponsored by Facebook - Washington on edge amid SCOTUS vacancy This week: Supreme Court fight over Ginsburg's seat upends Congress's agenda MORE (R-Tenn.) took the unusual step last week of publicly urging Trump to back down. He called on the president to reverse the emergency declaration and instead use transfer authorities that are already granted to him to find money for the wall.

“There is time for the president’s lawyers to take another look and determine whether we can both build the 234 miles of border wall that the president has requested and avoid this dangerous precedent,” Alexander, who is retiring at the end of the current Congress, said in a closely watched floor speech.

Alexander said Trump should find a way to let Republicans “who want to support him on border security be able to do that” while also “keeping our oath to the Constitution.”

Senate Majority Leader Mitch McConnell Addison (Mitch) Mitchell McConnellPelosi: Trump hurrying to fill SCOTUS seat so he can repeal ObamaCare Senate GOP aims to confirm Trump court pick by Oct. 29: report Trump argues full Supreme Court needed to settle potential election disputes MORE (R-Ky.) is expected to give a resolution blocking Trump’s emergency declaration a vote before lawmakers leave for a recess on March 15. GOP aides say the vote is more likely to happen next week, giving Republicans just under two weeks of breathing room to negotiate.

Republicans in both chambers have criticized the Trump decision as an assault on Congress’s authority that could lead a Democratic president to circumvent lawmakers to take action on climate change or gun control.

Paul, who joins three other Senate Republicans so far in publicly backing the resolution of disapproval, said he couldn't support giving a president "extra-constitutional powers."

“I can’t vote to give the president the power to spend money that hasn’t been appropriated by Congress. We may want more money for border security, but Congress didn’t authorize it. If we take away those checks and balances, it’s a dangerous thing,” he said, according to the Bowling Green Daily News.

In addition to Paul, GOP Sens. Susan Collins Susan Margaret CollinsSenate GOP aims to confirm Trump court pick by Oct. 29: report The Hill's Campaign Report: GOP set to ask SCOTUS to limit mail-in voting Senate GOP sees early Supreme Court vote as political booster shot MORE (Maine), Lisa Murkowski Lisa Ann MurkowskiSenate GOP aims to confirm Trump court pick by Oct. 29: report Senate GOP sees early Supreme Court vote as political booster shot Pence defends Trump's 'obligation' to nominate new Supreme Court justice MORE (Alaska) and Thom Tillis Thomas (Thom) Roland TillisThe Hill's Campaign Report: GOP set to ask SCOTUS to limit mail-in voting OVERNIGHT ENERGY: EPA head questions connection of climate change to natural disasters | Pebble Mine executives eye future expansion in recorded conversations | EPA questions science linking widely used pesticide to brain damage in children Liberal super PAC launches ads targeting vulnerable GOP senators over SCOTUS fight MORE (N.C.) have said they will join all 47 members of the Democratic Caucus in supporting a resolution blocking the emergency declaration.

Roughly a dozen GOP senators are also on the fence about the resolution, leaving open the possibility that supporters could pick up additional Republican votes.

Alexander, despite warning that Trump’s emergency declaration was creating a “constitutional crisis,” declined to say last week if he would vote for a resolution of disapproval.

“I will announce how I’m going to vote when I know what we’re going to be voting on,” Alexander said.

“I learned a long time ago in the United States Senate it’s not wise to announce how you’re going to vote on a vote you may never have to take."

Republicans are privately discussing if they could make changes to the resolution of disapproval.

Sen. Roy Blunt Roy Dean BluntSocial media platforms put muscle into National Voter Registration Day Senate GOP faces pivotal moment on pick for Supreme Court This week: Supreme Court fight over Ginsburg's seat upends Congress's agenda MORE (R-Mo.), a member of GOP leadership, said he had not yet decided how he was going to vote and that he was waiting to see “what our other options are.”

Sen. Ron Johnson Ronald (Ron) Harold Johnson CIA found Putin 'probably directing' campaign against Biden: report This week: Supreme Court fight over Ginsburg's seat upends Congress's agenda GOP set to release controversial Biden report MORE (R-Wis.), the chairman of the Homeland Security and Governmental Affairs Committee, added that Republicans have discussed if they could come up with an alternative, adding that he wanted to find a way to express support for border security.

“I want to express support for better borders, better border security,” he said. “If we can find a way to do that in our resolution that would be a good thing.”

Any attempts to amend the resolution of disapproval would likely face tricky procedural hurdles.

Sen. John Cornyn John CornynThe Hill's Campaign Report: GOP set to ask SCOTUS to limit mail-in voting Liberal super PAC launches ads targeting vulnerable GOP senators over SCOTUS fight Senate GOP faces pivotal moment on pick for Supreme Court MORE (R-Texas) acknowledged that Republicans had discussed trying to make changes but that they had run into roadblocks and he still anticipated Trump would need to use a veto. Blunt separately signaled that the difficulty of getting new language approved the parliamentarian could box them out of making changes.

The House resolution of disapproval, approved in a 245-182 vote, has been sent to the Armed Services Committee where Sen. James Inhofe James (Jim) Mountain InhofeChamber of Commerce endorses McSally for reelection Overnight Defense: Top admiral says 'no condition' where US should conduct nuclear test 'at this time' | Intelligence chief says Congress will get some in-person election security briefings Top admiral: 'No condition' where US should conduct nuclear test 'at this time' MORE (R-Okla.) says he does not plan to give it a hearing or a markup.

Trump has pledged to veto a resolution blocking his emergency declaration if it reaches his desk and appeared to send a recent warning shot to any Republicans weighing voting against him.

He characterized a vote for the resolution to block his emergency declaration as a “very dangerous thing” because it would undercut border security.

“I really think that Republicans that vote against border security and the wall, I think you know, I’ve been okay at predicting things, I think they put themselves at great jeopardy,” he told Fox News’s Sean Hannity.

With a resolution blocking Trump’s emergency declaration expected to fall short of overriding veto, Republicans are already turning their attention to separate legislation spawned out of an intense separation of powers debate.

A spokesman for Sen. Mike Lee Michael (Mike) Shumway LeeMcConnell shores up GOP support for coronavirus package McConnell tries to unify GOP Davis: The Hall of Shame for GOP senators who remain silent on Donald Trump MORE (R-Utah), who has yet to say how he’ll vote, confirmed that the Utah senator is working to draft legislation but declined to provide specifics.

“[It’s] related to how emergencies can be canceled. Making it easier for Congress to cancel an emergency declaration,” the aide added.

Blunt noted that he brought up during a caucus lunch that Congress might have “overreacted” to a Supreme Court ruling in the 1980s, after which they added the requirement that a president must sign the bill and could also veto it.

And Cornyn added he would be “very interested” in legislation that reins back in “across the board” some of the authority Congress had delegated to the executive branch.

“I’m not talking about this specific instance with the border security, but I think generally speaking this has been a little bit of a wake-up call,” he said. “I’m certainly interested in talking about it.”