When the entire Internet gets angry, Congress takes notice. Both the House and the Senate on Friday backed away from a pair of controversial anti-piracy bills, tossing them into limbo and throwing doubt on their future viability.

The Senate had been scheduled to hold a proceedural vote next week on whether to take up the Protect IP Act (PIPA) — a bill that once had widespread, bipartisan support. But on Friday, Senate Majority Leader Harry Reid said he was postponing the vote “in light of recent events.”

Meanwhile, the House of Representatives said it is putting on hold its version of the bill, the Stop Online Piracy Act (SOPA). The House will “postpone consideration of the legislation until there is wider agreement on a solution,” House Judiciary Committee Chairman Lamar Smith said in a written statement.

The moves came after several lawmakers flipped their position on the bills in the wake of widespread online and offline protests against them.

Tech companies, who largely oppose the bills, mobilized their users this week to contact representatives and speak out against the legislation. Sites including Wikipedia and Reddit launched site blackouts on January 18, while protesters hit the streets in New York, San Francisco, Seattle and Washington, D.C. Google drew more than 7 million signatures for an anti-SOPA and PIPA petition that it linked on its highly trafficked homepage.

The tide turned soon after the protest, and both bills lost some of their Congressional backers.

“I have heard from the critics and I take seriously their concerns,” Smith said Friday in a prepared statement. “It is clear that we need to revisit the approach on how best to address the problem of foreign thieves.”

PIPA and SOPA aim to crack down on copyright infringement by restricting sites that host or facilitate the trading of pirated content. (Click here for our explainer: What SOPA is and why it matters.)

Backed by media companies, including CNNMoney parent Time Warner, the bills initially seemed on the fast track to passage. PIPA was approved unanimously by a Senate committee in May.

But when the House took up its own version of the bill, SOPA, tech companies began lobbying heavily in opposition — an effort that culminated in this week’s demonstrations.

Reid hinted that PIPA may not be dead yet, saying: “There is no reason that the legitimate issues raised by many about this bill cannot be resolved.”

Meanwhile, alternative legislation has also been proposed. A bipartisan group of senators introduced the Online Protection and Enforcement of Digital Trade Act (OPEN) on January 18 — the same day as the Wikipedia site blackout.

Among other differences, OPEN offers more protection than SOPA would to sites accused of hosting pirated content. It also beefs up the enforcement process. It would allow digital rights holders to bring cases before the U.S. International Trade Commission (ITC), an independent agency that handles trademark infringement and other trade disputes.

California Republican Darrell Issa introduced OPEN in the House, and Oregon Democrat Ron Wyden introduced the Senate version. OPEN‘s backers had posted the draft legislation online and invited the Web community to comment on and revise the proposal.

Soon after SOPA and PIPA were tabled, Issa released a statement cheering “supporters of the Internet” for their protest efforts.

He wrote: “Over the last two months, the intense popular effort to stop SOPA and PIPA has defeated an effort that once looked unstoppable but lacked a fundamental understanding of how Internet technologies work.”