Republican hopes of a turnabout rested largely on a familiar phenomenon of the Trump administration - an unexpected change in mind, as he's done in congressional battles over health care and immigration.
Key to quelling the revolt is legislation drafted by Sen. Mike Lee (R-Utah) that would have amended the National Emergencies Act to automatically end presidential emergency declarations after 30 days unless Congress votes to extend the emergency.
"The House will not take up this legislation to give President Trump a pass [on the emergency declaration]", Pelosi said in a statement.
Tillis and three other GOP senators have said they would vote with Democrats to support the resolution blocking Trump's border emergency - enough to assure its passage, assuming all Democrats vote "yes" as expected.
The resolutions are both privileged, which means they can not be stopped by Senate Majority Leader Mitch McConnell, a Republican from Kentucky.
But approval of the resolution would highlight a clash in which Trump was being forced to protect his signature campaign promise by vetoing legislation sent to him by a Republican-led Senate.
The speaker had previously taken a cautious tone when discussing possibly impeaching the president - a path widely viewed as politically fraught, though its supporters say with so few examples in American history it remains to be seen how a new trial would play out in the public. "We're looking for ways to get the power back where it constitutionally belongs".
"We'll see whether or not I have to do the veto. And that's not even an exhaustive list". Their concerns are shared by others privately in the party. Congress can vote to block an emergency declaration, but the two-thirds majorities required to overcome presidential vetoes make it hard for lawmakers to prevail.
Pelosi's office did not immediately respond to a request for comment.
Tyrann Mathieu to sign three-year, $42m deal with Kansas City Chiefs
Houston lost safety Tyrann Mathieu to the Kansas City Chiefs and defensive back Kareem Jackson to the Denver Broncos. His reported agreement with the Chiefs is for $42 million over three years, according to ESPN's Adam Schefter.
"I said: 'Why don't you use this for impeachment?'" Trump said he asked Pelosi.
"There's a lot of discomfort with the law", McConnell told reporters Tuesday. Democrats noted that America's border deficiencies have been debated for decades, and in making the declaration, Trump himself said he "didn't have to do it".
FILE - People gather during a protest against U.S. President Donald Trump's declaration of a national emergency to build a border wall, outside Trump International Hotel & Tower in Manhattan, New York. Thom Tillis of North Carolina, Susan Collins of Maine, Lisa Murkowski of Alaska and Kentucky's Rand Paul. So far, 14 other Republicans support the bill in the Senate. Ted Cruz (R-Texas), who remains publicly undecided on the vote, told HuffPost on Tuesday. A Tillis aide did not return messages left for him.
Meanwhile, the White House has stepped up its engagement with Republican senators in other ways.
Besides Lee, four have said they would vote no: Sens. That has been "helpful", said Lankford, who added that he plans to oppose the disapproval measure.
"The president's doing what he feels is right".
"I'm not for impeachment". "But we really have abdicated our responsibility".
Chances seem to be improving that President Donald Trump might avoid an expected rejection by Congress of his effort to divert more money to building barriers along the Mexican border.
Under a 1976 law, presidents have wide discretion in determining when a national emergency has occurred.
"It is about Border Security and the Wall [stopping Crime, Drugs, etc.], not Constitutionality and Precedent", the president recently wrote on Twitter.