Speaker Nancy Pelosi said on Thursday her party will use immigration reform as a "battle cry" going forward, after the House passed a $4.6 billion emergency humanitarian border bill over the angry objections of progressive Democrats, sending it to President Donald Trump for his signature.

The measure passed 305-102, marking the first time in the 116th Congress where more House Republicans helped pass a piece of legislation on a recorded vote than Democrats.

While lawmakers expressed outrage this week after a photograph emerged of a drowned man lying face-down in the Rio Grande with his lifeless toddler daughter wrapped in his t-shirt, freshman Democratic Rep. Ilhan Omar said Congress “did nothing to stop that from happening.”

“What we did today is continue to allow the atrocity to take place,” Ilhan, D-Minn., warned. “We’ve sent money that we don’t know if it’s going to continue to be used to put proper beds, to buy toothpaste, to assist these children in any kind of way and their families.”

Michigan freshman Democrat Rep. Rashida Tlaib blamed Senate Democrats for joining Republicans instead of negotiating with House Democrats.

“If we’re not going to hold them accountable and say they have these set standards they have to abide buy, then how are we addressing the humanities crisis?” she wondered. “We’re just throwing money at folks and not telling them exactly what they’re supposed to be doing with it.”

Pelosi said she "reluctantly" urged Democrats to pass emergency spending bill, approved in a bipartisan vote Wednesday by the GOP-controlled Senate, that would send humanitarian relief to the southern border, reversing course and abandoning a Democratic effort to amend the Senate version.

"The children come first. At the end of the day, we have to make sure that the resources needed to protect the children are available," Pelosi wrote in a "Dear Colleague" letter Thursday afternoon. "Therefore, we will not engage in the same disrespectful behavior that the Senate did in ignoring our priorities. In order to get resources to the children fastest, we will reluctantly pass the Senate bill."

That decision was immediately met with criticism from progressives Democrats, who called the package "entirely insufficient to protect vulnerable children in our care.”

Rep. Mark Pocan, the co-chair of the Congressional Progressive Caucus, said he thinks the House, scheduled to go on recess Thursday for the July Fourth holiday, should have stayed another day in Washington to fight to amend the Senate bill.

“It’s unfortunate that we couldn’t just stick around and get this done,” Pocan, D-Wis., said. “President Trump has never stood by his word on pretty much anything on the border. He’ll go to another rally and foam at the mouth about the issue rather than deal with what’s going on. Everyone should be concerned about kids that aren’t given blankets, aren’t given soap, aren’t given toothbrushes. It’s ridiculous.”

After Pelosi announced the shift, freshman Democratic Rep. Alexandria Ocasio-Cortez of New York lashed out on Twitter.

Just 129 House Democrats voted in favor of the border package – accounting for about 55 percent of Speaker Nancy Pelosi’s caucus. Majority Leader Steny Hoyer and Whip Jim Clyburn voted in favor of the bill, but the next ring of leaders opposed it, including No. 4 Ben Ray Lujan, who is running for U.S. Senate, and Rep. Hakeem Jeffries, the Democratic Caucus Chairman who many Democrats believe is on a fast track to replace Pelosi some day.

Republicans carried the water on this vote, bringing 176 ayes to the floor to help it pass. Just seven Republicans opposed the measure, while 95 Democrats voted against the bill. Twenty-five lawmakers skipped the vote, beginning their 11-day recess a little earlier than those who stayed for the vote.

Democrats don't walk away completely empty-handed.

Two sources familiar with a conversation between Vice President Mike Pence and Pelosi confirm the administration agreed to two key demands from the speaker -- that Members would be notified within 24 hours after the death of a child in custody, and to a 90-day time limit on children spending time in an influx facility, where migrants are temporarily held while they await transfer to facilities operated by Health and Human Services.

Rep. Dan Kildee, one of the 95 Democrats who voted for the bill, said “at the end of the day you have to do something.”

“Walking away and doing nothing, knowing that there really is a humanitarian crisis at the border, it needs an answer,” Kildee, D-Mich., said. “And I can’t face myself and say I wasn’t willing to do what I could do because we didn’t have the votes to do what I wanted to do.”

Rep. Andy Levin, a freshman Democrat, said he voted no “with a heavy heart.”

“I’m absolutely intent on getting money to these kids,” he said. “I’m very concerned now that the Trump administration will use the money to advance its punitive approach, and incarcerate more people, hold more people in these horrifying conditions and so I voted no.”

The showdown dragged on for most of the morning, before a group of moderate Democrats and Republicans banded together to pressure Pelosi to pass the Senate's bipartisan package -- absent additional protections for migrant children and restrictions on funding for Immigration and Customs Enforcement.

“Given the humanitarian crisis at the border, the Problem Solvers Caucus is asking for the immediate consideration on the House Floor today of HR 3401, as amended by the Senate,” the caucus wrote in a statement.

With 23 Democrats on-board, Pelosi's majority had evaporated, giving her little choice than to pull the amendment from the floor imposing changes to the Senate package.

Asked Thursday morning whether she’d put the Senate-passed bill on the floor of the House for a vote, Pelosi told reporters “cooperation is a two-way street,” refusing to rule out a vote on the upper chamber’s bipartisan package.

“We’re looking forward to having a conversation, further conversations on this matter. One step at a time,” Pelosi, D-Calif., said.

Pelosi then spoke to Vice President Mike Pence for nearly an hour starting at 11:20 a.m. and briefed her leadership on the discussion Thursday afternoon, according to a senior Democratic leadership aide.

“There may be some things that we would yield on, depending on the objection they may have,” she told reporters before the phone call. "This is a day. This is not the end of this discussion."

Earlier Thursday, after Senate Majority Leader Mitch McConnell threatened to kill an amendment House Democrats are hoping to add to a bipartisan compromise passed by the Senate on Wednesday, Pelosi warned McConnell that he'd own the public blowback from stopping the bill amid the crisis.

As she left the House chamber and walked back to her office, Thursday morning, ABC News asked her about McConnell's floor speech Thursday morning, in which he threatening to kill the Democrats’ amendment.

“I don’t think there’s room for any threats here. We’re not threatening him,” Pelosi said. “This is a moral imperative. It’s not about threats or conditions or anything like that. It’s about what’s doing right for the children and not taking the path of least resistance.”

Ahead of the House vote Thursday, McConnell said "it is crystal-clear" that some of the Democratic demands "would drag this bipartisan bill way back to the left and jeopardize the Shelby-Leahy consensus product that unified the Senate and is so close to becoming law."

"If House Democrats send the Senate back some partisan effort to disrupt our bipartisan progress, we will simply move to table it," McConnell promised. "We already have our compromise. The Shelby-Leahy Senate bill is the only game in town. It’s time to make it law."

But many House Democrats were not satisfied with that legislation, and wanted changes to add additional child migrant protections, while reducing spending in the bill carved out for the Defense Department and slashing $81 million in funds for Immigration and Customs Enforcement.

Pelosi was unmoved by McConnell's threat, and warned he would own the public reaction if Congress is unable to put a bill on the president's desk before the Independence Day recess.

“I commend the superior knowledge of the House members in writing a bill that does much more for the children," Pelosi said. "So whatever he wants to do, he has to know, the public will know that he came down against the interest of the children.”

Asked for her reaction to a photo showing two drown migrants — a man with his toddler daughter tucked inside his t-shirt face-down in the Rio Grande — and whether anyone should be blamed for their deaths, Pelosi paused — for six seconds — before answering:

“It’s not a question of blame. It’s a question of being prayerful and understand the consequences of policy,” she said, pointing at the administration’s so-called “metering” policy that limits asylum claims at border checkpoints. "I just think it’s such a shame for that to be the face of America around the world."

ABC News' Trish Turner and Jordyn Phelps contributed to this report