Usually, casting a vote in the House of Representatives has all the drama of a visit to the ATM. Legislators swipe a plastic ID card, punch a button, and watch a small “N” or “Y” appear alongside their name on the House’s back wall.

But on Monday, people wept to see it done.

Rep. Gabrielle Giffords (D-Ariz.), grievously wounded by a gunman in her home town of Tucson seven months ago, made a surprise return to the House floor Monday evening, to cheers and hugs from her colleagues.

One legislator dropped his dignity and climbed on a chair to see what the fuss was about. Another, seeing the commotion, assumed the president had arrived. But it was Giffords, with shorter hair than when she left, a bandage on her right wrist and the scars of trauma still visible on her head.

But she wore her congressional ID pin. She had come to cast a vote to raise the nation’s debt ceiling.

The lawmaker whose near-
lethal injuries had come to echo the rancor of the political times had returned to Washington at a moment that seemed to triumph over the bitterness.

“There is a basic humanity here, man,” said Vice President Biden, who was at the Capitol when Giffords arrived. At the end of a long and bitter fight over the debt limit, Giffords was encircled by legislators from both sides.

“I have closely followed the debate over our debt ceiling and have been deeply disappointed at what’s going on in Washington,” Giffords said in a statement later. “I had to be here for this vote. I could not take the chance that my absence could crash our economy.”

Giffords, 41, is in her third term in Congress. The last time she voted was on Jan. 7, on a routine bill that attracted little notice. A red “N” appeared next to her name, and Giffords left town for the weekend.

At 10:10 the next morning, Giffords was standing in the parking lot of a Safeway in Tucson, about to begin an event called “Congress on Your Corner.” According to police, 22-year-old Jared Lee Loughner walked up to the crowd. He had a Glock 19 semi­automatic handgun.

Giffords was shot in the head, and bystanders were then gunned down. Six people died, including a congressional aide, a federal judge and a 9-year-old girl. Thirteen more were wounded.

In Giffords’s absence, the House took 678 votes. In each, the space next to her name remained blank.

On Monday, the first hint that that might change came in messages on Twitter. “The #Capitol looks beautiful and I am honored to be at work tonight,” Giffords wrote on the microblogging site.

The previous evening, Rep. Debbie Wasserman Schultz (D-Fla.), Giffords’s closest friend in Congress, had received a call from Giffords’s husband, Mark Kelly, who said Giffords was following the debt debate. Even when it became clear her vote was not going to be pivotal, Giffords remained eager to weigh in on the significant issue, Wasserman Schultz said.

“We had all prayed she would be able to do this,” said Wasserman Schultz. “It was a huge step.”

When she arrived, Giffords met briefly with House Speaker John A. Boehner (R-Ohio) outside the chamber. Then the doors on the Democratic side opened to wild applause at something the rest of the House couldn’t see.

“I did something that was not too congressional,” said Rep. James E. Clyburn (S.C.), the No. 3 Democrat. “I stood up in the seat to see what it was about.”

Word spread. Rep. Peter Welch (D-Vt.) called it “the best experience I’ve had in Congress.”

Giffords walked a few yards through the crowd to a voting machine and punched the button. Heads turned toward the back wall, where a green “Y” appeared next to her name.

It read like an existential declaration. Giffords: Yes.

Staff writers Rosalind S. Helderman, Sandhya Somashekhar and David Brown contributed to this report.