The House on Monday approved bipartisan legislation to raise the $14.3 trillion debt ceiling and reduce long-term budget deficits, endorsing the agreement President Obama struck with Republican leaders.

The vote also featured the surprise and emotional return of Rep. Gabrielle Giffords, the Arizona Democrat who survived an assassination attempt earlier this year. She cast her vote in favor of the measure to a standing ovation from both parties.

The bill now heads for a Tuesday vote in the Senate, which is expected to act less than a day before the U.S. government confronts an unprecedented default on its debt.

The vote was 269-161, as Republicans largely carried the measure over the opposition of half of the Democratic Caucus.

Minority Leader Nancy Pelosi (D-Calif.) backed the bill, as did Minority Whip Steny Hoyer (D-Md.), but neither leader made a public effort to win Democratic support. Sixty-six Republicans voted no, while 95 Democrats supported it and 95 opposed.

After months of legislative wrangling, House passage of the debt-limit bill followed a frantic effort by Republican leaders and the White House to secure the necessary votes for a pact they finalized on Sunday. Obama dispatched Vice President Biden to sell the deal to congressional Democrats, while House Speaker John Boehner (R-Ohio) briefed House Republicans for a second straight day.

The dramatic appearance of Giffords overwhelmed the House chamber, momentarily reducing the result of the crucial vote to an afterthought.

With the bill more than 40 votes short of passage, Boehner left the House floor and walked around the chamber to meet Giffords, who was escorted in by Rep. Debbie Wasserman Schultz (D-Fla.), a close friend and the chairwoman of the Democratic National Committee. Walking haltingly, Giffords entered the chamber and was immediately swarmed by members, including Pelosi. Lawmakers stood and applauded for several minutes, and dozens of Democrats joined Giffords in casting yes votes to put the measure well over the top. Pelosi could be seen wiping tears from her eyes, and Biden entered the hall to see Giffords.

Earlier Monday, Boehner met separately with GOP members of the House Armed Services Committee, who voiced concerns about the level of military cuts in the bill. "This is the best defense number we're going to get," the Speaker said he told the committee. The panel's chairman, Rep. Buck McKeon (R-Calif.), released a statement supporting the legislation, albeit "with deep reservations."

House Republican leaders heralded the debt-limit bill as an imperfect measure that would usher in a culture change in Washington spending.

The bill creates a process for increasing the debt ceiling by at least $2.1 trillion through 2012 while reducing the deficit by nearly $1 trillion over 10 years. The legislation also establishes a 12-member joint congressional committee that must identify, by Nov. 23, an additional $1.5 trillion in deficit reduction. If the committee fails, or if Congress does not enact its recommendations, the legislation triggers automatic cuts both to entitlement and defense programs.

"The big win here for us and for the American people is the fact that there are no tax hikes in this package," House Majority Leader Eric Cantor (R-Va.) said. He said the bill is "not perfect," but likened the effort to push back at Washington's culture and reduce federal spending to "turning around an aircraft carrier."

Republicans said they achieved two-thirds of the spending cuts they sought in their 2012 budget resolution.

"The numbers relative to the problem are minimal, but the directional change is huge," said Rep. Jeb Hensarling (Texas), the chairman of the House Republican Conference.

Among Democrats who voted for the measure, virtually none of them did so enthusiastically. "I'm not happy with it, but I'm proud of some of the accomplishments contained in it and that is why I am voting for it," Pelosi said in a floor speech shortly before the vote.

Pelosi and other Democratic leaders argued more for what the bill excluded than what it contained. The former Speaker said the party had succeeded in preventing benefit cuts to the core safety-net programs of Medicare, Medicaid and Social Security.

"Please think of what would happen if we defaulted," Pelosi said in a message to fellow Democrats, warning that the middle-class Americans the party fought to protect would wind up as "collateral damage" in an economic calamity.

"I would urge you to consider voting yes, but I completely respect the hesitation that members have about this," Pelosi said.

House liberals condemned the measure as a capitulation to the GOP. The chairman of the Congressional Black Caucus, Rep. Emanuel Cleaver (D-Mo.), compared it to a "sugar-coated satan sandwich." In an interview with ABC News, Pelosi did not dispute the characterization, adding that it came with a side of "Satan fries."

Rep. Luis Gutierrez (D-Ill.) said Republicans acted as "arsonists" in the debt-limit debate, but he said he would vote for the bill anyway.

"The arsonists must be stopped," he said. "We have a choice - compromise or chaos - and I'm choosing compromise. I will vote for the bill and hope we can close this distasteful chapter in American politics."

Cantor said the House planned to leave Washington for its August recess after voting on the legislation Monday.

While GOP leaders voiced confidence in the hours leading up to the vote, they engaged in a veritable staring contest with Democrats over which party would put the bill over the top.

After the Democratic leadership indicated it would not whip its members in support, Boehner spoke up.

"I would remind all of you that this is not just an agreement between the president and myself," Boehner said in an afternoon press conference. "This is an agreement between the bipartisan leaders of this Congress and the president of the United States, and all the leaders have a responsibility, because they've all signed off on the agreement, to bring sufficient votes to make sure it passes."

Democrats prepare for Gabrielle Giffords reelection  

Democrats are laying the campaign groundwork so Rep. Gabrielle Giffords "doesn't have to start from scratch" if she decides to run for re-election, her close friend Rep. Debbie Wasserman Schultz said on Tuesday. 

"We're certainly getting her ready to make sure she can run for re-election at the point that they're ready to decide on that," the Florida congresswoman and Democratic National Committee chairwoman said on MSNBC's "Morning Joe" the morning after Giffords surprise appearance on the House floor on Monday night.

"She continues to focus on her recovery ... she's going to continue to work hard in that recovery. As you've seen, she's got the heart of a lion, made remarkable progress," Wasserman Schultz said. "But her supporters in Arizona and across the country, her colleagues, are making sure that she doesn't have to start from scratch when she makes that decision."

Wasserman Schultz's comments came as Giffords spokesman CJ Karamargin said in a brief statement that "Congresswoman Giffords is focused on her recovery. No decision has been made about 2012." The statement came after CBS News reporters said on Twitter at about 7 a.m. ET that Giffords had decided to run.

In another appearance Tuesday morning, on CBS's "Early Show," Wasserman Schultz said that Giffords is "working hard" to return to Congress and went back to Houston soon after the vote to do all her outpatient therapies during the day Tuesday. "There's no clear predictions," the DNC chairwoman said. "But this is just yet another example" of Giffords's progress.

Giffords was "absolutely overwhelmed" when she returned to the House chamber Monday night for the first time since suffering a gunshot wound to the head in January, Wasserman Schultz said in an appearance earlier Tuesday morning on NBC's "Today." "When she came in the chamber she was excited, she was greeting people all way up the stairs."

Wasserman Schultz, who also appeared on ABC's "Good Morning America" and CBS's "Early Show," said that Giffords's husband, NASA astronaut Mark Kelly called her on Sunday night to say that Giffords had been following the debt ceiling debate closely.

Giffords "felt strongly if her vote was pivotal she needed to make sure that she came to Washington." Wasserman Schultz said on ABC.

The recovering congresswoman "didn't have too many worries" about whether the bill would pass, the DNC chairwoman said on NBC. Ultimately, she "decided that either way, it was important for her constituents in the 9th District in Arizona to have their voice heard and recorded on probably the most important [vote] that we would cast this Congress," Wasserman Schultz said on ABC.

During the debt ceiling debate, "the most grizzled hardened hearts harden[ed] even further," she said. But "they all melted when she walked in the chamber.... We have a lot of applause for various reasons in the house chamber, never like this. It was thundering."

"It was such a moment that the Congress needed, that the country needed. Everyone's been praying for this moment," Wasserman Schultz added on NBC. "Hopefully it's an opening and an opportunity for us in the second half of this effort as commission begins to meet for us to really come together and put forward a balanced plan that makes sure we can get our economy really on the way again to turning around and recovering."