Senate Republicans blocked a bill on Wednesday to pair tens of billions of dollars in aid to Ukraine and Israel with stringent border security measures, thwarting a compromise they had demanded in the latest setback to the emergency national security spending package.
But Democrats moved quickly to try to salvage the aid from becoming a casualty of former President Donald J. Trump’s political campaign, pivoting to advance a stand-alone foreign aid bill stripped of the immigration measures. In a day of whiplash on Capitol Hill, Senator Chuck Schumer, Democrat of New York and the majority leader, set a vote on that alternative, which Democrats and Republicans alike said they hoped would be successful.
But nothing is quick in the United States Senate, and by Wednesday evening lawmakers were stuck in yet another stalemate as Republicans slow-walked business on the floor while they regrouped. They held open a procedural vote for hours as they sought assurances from Democrats that if they voted to allow the stripped-down aid bill to move forward, they would be allowed to propose changes.
Senator John Cornyn, Republican of Texas, told reporters that there were ongoing discussions about how the money to Ukraine and Israel would be distributed.
Other Republicans appeared to be stuck in an endless loop, continuing to demand border changes — only hours after voting to tank the aid package that contained them. Senator Lindsey Graham, Republican of South Carolina, was demanding the chance to add back border provisions. Senator Tim Scott of South Carolina told Fox News he would oppose the stand-alone foreign aid bill because “we should first secure our southern border.”
After 7 p.m., Mr. Schumer said the Senate was recessing to “give our Republican colleagues the night to figure themselves out.” He said he would hold the vote on the foreign aid on Thursday afternoon.
Despite the delay, there were glimmers of hope that the package of aid for Ukraine and Israel would eventually move forward. A bipartisan vote to advance the aid package would represent a remarkable turnaround after months of stalemate and likely put the measure on track for passage in the Senate within days.
The measure would send $60.1 billion to Ukraine for its war against Russian aggression, $14.1 billion in security assistance for Israel and $10 billion in humanitarian aid for civilians of global crises, including Palestinians and Ukrainians.
The effort to get the legislation back on track came after Republicans blocked a bill that paired the foreign aid with stringent border security measures they had demanded. That plan, hashed out over four months of painstaking bipartisan negotiations, hemorrhaged Republican support after Mr. Trump vocally opposed it. It failed on a 50-to-49 vote, falling short of the 60 votes it would have needed to advance, as all but four Republicans rejected it.
Even if Democrats succeed in resurrecting the aid bill in the Senate, it still faces stiff headwinds in the Republican-led House, where right-wing lawmakers are opposed to sending additional assistance to Ukraine. Some have even threatened to oust Speaker Mike Johnson if he brings any bill to the floor that includes it.
Members of both parties who have championed the package have warned that the fate of Eastern Europe hangs in the balance, alongside America’s reputation on the world stage, if Congress fails to move ahead.
Mr. Schumer made it clear early Wednesday morning that he planned to move quickly to advance a “Plan B” that he had put in motion earlier in the week when it became clear the border-Ukraine deal would not have the necessary 60 votes to move forward.
“Republicans have said they can’t pass Ukraine without border. Now they say they can’t pass Ukraine with border. Today, I’m giving them a choice,” Mr. Schumer said on the Senate floor on Wednesday before the back-to-back votes. He added, “I urge Republicans to take yes for an answer.”
Mr. Schumer’s maneuver meant that Republicans had to decide whether they wanted to vote twice in one day to block the measure, a grim prospect for a party that on Tuesday suffered a series of humiliating setbacks that showed its inability to govern.
The odd dynamic meant that the border, once an issue that united Republicans, ultimately helped to pave the way for more of them to support funding Ukraine. On Wednesday afternoon, Senator Thom Tillis, Republican of North Carolina, and Senator Roger Wicker, Republican of Mississippi, both said they would vote for the stand-alone bill after opposing the border-Ukraine package.
The negotiators on the border deal, who spent the past four months putting together what they pitched as a once-in-a-generation opportunity to make conservative policy changes on immigration, vented their frustration on the Senate floor ahead of its demise.
Senator James Lankford of Oklahoma, the lead Republican negotiator, bemoaned how politics had surpassed policy after Mr. Trump inserted himself into the debate, making it clear he did not want lawmakers to take any action on the border as he ran a campaign that once again made immigration one of its central planks.
Holding up the pen he was given when he was sworn in as a senator, Mr. Lankford said: “There’s no reason for me to have this pen if we’re just going to do press conferences. I can do press conferences from anywhere. But we can only make law from this room.”
As he outlined the details of his bill, Mr. Lankford conceded that it had become impossible to counter the misinformation about it that spread online and was amplified by right-wing supporters of Mr. Trump.
He said that one prominent media personality on the right told him directly, “‘if you try to move a bill that solves the border crisis during this presidential year, I will do whatever I can to destroy you.’” Mr. Lankford added, “They have been faithful to their promise and done everything they can to destroy me in the past several weeks.”
Senator Kyrsten Sinema, the Arizona Democrat turned independent who has made it her signature in Congress to work across the aisle with Republicans, also criticized them on the Senate floor. She argued that the G.O.P. had made it clear it was interested in little more than political theater.
“After all those campaign photo ops in the desert, after all of those trips to the border, this crisis isn’t actually much of a crisis after all,” said Ms. Sinema, who served as a lead negotiator on the bipartisan bill. She warned any Republican who wanted to use the southern border as a backdrop for future political events: “Don’t come to Arizona. Take your political theater to Texas. Do not bring it to my state.”
Mr. Lankford was ultimately joined by only three other Republicans in voting to allow the bill to advance. The others were Senators Lisa Murkowski of Alaska, Susan Collins of Maine and Mitt Romney of Utah. Senator Mitch McConnell, Republican of Kentucky and minority leader, voted against a bill that he had championed every step of the way until it became politically untenable.
For Mr. McConnell, who has made it his singular priority this Congress to continue funding the war effort in Ukraine, the immigration deal was ultimately beside the point. He was expected to vote in favor of the stand-alone foreign aid bill.
On Wednesday morning, Mr. Johnson would not say whether the House would take up the stand-alone national security bill, if and when it passed the Senate. “We’ll see what the Senate does; we’re allowing the process to play out,” Mr. Johnson told reporters.
That was a strikingly different tone from his stance on the border and Ukraine package, which he had repeatedly called “dead on arrival” in the House even before he had seen its text. On Tuesday night, Republicans failed to push through a $17.6 billion bill to send military assistance only to Israel, a failure that Mr. Johnson tried to pin on Democrats.
Mr. Johnson, however, is facing immense pressure on his right to reject the national security package. Representative Marjorie Taylor Greene, Republican of Georgia, has threatened to oust him from the speakership if he brings any bill to the floor that includes funding for Ukraine.
Karoun Demirjian and Carl Hulse contributed reporting.