After hammering out a deal on a now-$780 billion stimulus package this evening, Senate leaders believe they have a bill that likely can pass a Senate vote some time in the coming days.
Senate Majority Leader Harry Reid, D-Nev. said he will start the process toward a cloture vote on the stimulus Monday.
"We recognize that our plan isn't perfect," Sen. Ben Nelson, D-Neb., a key negotiator on the deal, told his fellow senators. "But I believe it's both responsible and realistic. It's stimulative and timely. It can help deliver economic recovery to the American people soon."
Nelson said negotiators went through the once-approximately-$900 billion package line by line to make tens of billions in cuts.
"We trimmed the fat, fried the bacon and milked the sacred cows," Nelson told the Senate, as it debated the revised bill into the evening.
The deal is expected to draw two or more Republican votes into the Democratic caucus to reach 60 votes or more -- the number needed to avoid a Republican filibuster.
Two Republican moderates, Sens. Susan Collins, R-Maine, and Arlen Specter, R-Pa., said this was a time for the Senate to come together.
"This debate is not about Republicans or about Democrats, it's not about our young president winning or losing, its about the American people," Collins said. "The American people don't want to see partisan gridlock."
"We have reduced the expenditures by $145 billion -- that's a lot of money," added Specter, pointing out that much of the money that will be cut was meant for popular programs, including tens of billions for education spending.
But their Republican colleagues questioned whether the minimal support from Republicans really was bipartisan.
"There are 40 Republican senators here," said Sen. John McCain, R-Ariz. "We now have two -- count them, two -- who have decided behind closed doors.
"I've been involved in a lot of bipartisan legislation around here," he added, "but I guarantee you, this is not bipartisan."
Senate Minority Leader Mitch McConnell, R-Ky., expressed doubts about whether the Senate bill really is pared down, considering tax cuts for house and auto purchases that senators added this week before making today's cuts.
"Even after those efforts, it is still roughly the same size as the [$819 billion] House bill," he said, guessing that the Senate version could rise to $827 billion with amendments.
"This is an extraordinary amount of money and a crushing debt for our grandchildren," McConnell said.
But the Obama White House has been pushing for senators to pass a stimulus bill, and tonight applauded the new compromise.
"On the day when we learned 3.6 million people have lost their jobs since this recession began, we are pleased the process is moving forward and we are closer to getting Americans a plan to create millions of jobs and get people back to work," said White House Press Secretary Robert Gibbs.
Weekend Vote After Day of Negotiations
There likely will be no vote on the bill tonight -- but more likely on Saturday or Sunday after further negotiation and debate. It's possible the final vote may slip to Monday.
However, officials emerging from a closed-door Democratic caucus meeting on the deal before the Senate debate were optimistic.
"I am pleased with this," said Sen. Barbara Boxer, D-Calif. "This is a strong package."
The agreement was spearheaded by a coalition of bipartisan senators aiming to reduce spending enough to get the Republican votes needed to pass the bill. The White House was also a chief negotiator, dispatching Rahm Emanual, the president's chief of staff, to Capitol Hill to try to shepherd a bill to sign by President's Day.
However, Sen. Reid., now may have to sell the trimmed-down bill to some Democrats, sources said as details of the deal emerged.
Senators got to the $780 billion number not only by taking out some spending programs targeted by Republicans, but also by shaving some of the broader state aid and narrowing the alternative minimum tax relief approved by the Senate earlier this week.
Sen. John Kerry, D-Mass., said that compromise is 42 percent tax cuts and 58 percent spending, according to a Reuters report.
While some Republicans and Democrats may have reached common ground with a deal, whatever bill is finally approved by the Senate must be reconciled with the $819 billion version passed in the House of Representatives with no Republican votes -- a process which promises further negotiation.
Obama Presses 'Sense of Urgency'
Earlier today, an impatient President Obama told a squabbling Congress that it would be "inexcusable and irresponsible" to delay passage of his economic stimulus bill and said the loss of nearly 600,000 jobs last month underlined the urgency of their vote.
"At the other end of Pennsylvania Avenue, members of the Senate are reading these same numbers this morning," said Obama today, citing statistics revealing that January brought the worst job losses since 1974.
"I hope they share my sense of urgency."
Obama called it "inexcusable and irresponsible to get bogged down in distraction and delay while millions of Americans are being put out of work."
"It is time for Congress to act," Obama said while announcing a new economic recovery advisory board. "It is time to pass an Economic Recovery and Reinvestment Plan to get our economy moving again."
Upon exiting a meeting in Senate Majority Leader Reid's office Friday afternoon before the evening compromise was reached, a disheartened Sen. Charles Schumer, D-N.Y., said on the Senate floor that "a bill may not even pass."
"We have some who want a number lower," Schumer said. "We have some who want a number higher. And the fights are over important issues like education and health care and roads and broadband and all of the things we think we need to get this economy working again, some short-term, some long-term."
Collins likewise suggested earlier in the day that the Senate faced new hiccups. Asked how she felt about the negotiations, Collins said, "Not as good as I felt earlier."
Obama had said earlier in the week he wanted the bill passed by today, but the Senate continued to disagree over how large the bill should be, whether certain programs should be eliminated and how much of the bill should consist of tax breaks.
"Broadly speaking, the package is the right size, it is the right scope, and it has the right priorities to create 3 to 4 million jobs, and to do it in a way that lays the groundwork for long-term growth," Obama said today.
The president also renewed a shot at Republicans that he first used Thursday, saying voters "did not choose more of the same in November. ... They did not send us here to turn back to the same tried and failed approaches that were rejected, because we saw the results. They sent us here to make change with the expectation that we would act."
Nelson seemed confident that the Senate would indeed take action.
"It is not slipping," said an upbeat Nelson after the meeting in Reid's office, noting it was always going to be difficult to create a package that was going to be palatable to both Republicans and Democrats.
"Fatigue plays a role," he said, implying that the length and intensity of the negotiations are taking a toll.
Earlier, Reid said the group of bipartisan senators trying to trim the $900 billion measure was making progress. Reid said that while he didn't agree with everything the group is proposing to cut down the bill, he respected its effort and believed the senators were trying to make the bill better.
"They have been genuine in their efforts," Reid said. "They have been responsible in their efforts. While I don't agree with everything they're trying to do, I agree with the efforts that they've made. And I think that we're going to be able to work something out. I feel very comfortable that we can do that.
"If we succeed, Mr. President, there's going to be a lot of credit to go around," Reid continued. "If we fail, there's going to be a lot of blame to go around. As I've said, our entire country will suffer and the world will suffer; we are the economy that drives the world economy."
Republican negotiators this morning were coming and going from Specter's Capitol Hill office, including Collins; Mel Martinez of Florida; Lisa Murkowski of Alaska; George Voinovich of Ohio; and Specter. Democrat Tom Carper of Delaware also was seen visiting the office.
"There is no perfect solution to what we're attempting," Reid said this morning. "There's no book we can check out of the library to say, 'This is what should be done.' There's no group of economists we can go to and tell them to prepare a paper in the next couple hours to give us directions what to do. We must do this on our own, and we will do this on our own."
ABC News' Jake Tapper, David Chalian and Michael S. James, and ABC News Radio contributed to this report.